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FAQs on Calcium and Alkalinity in Seawater 1

Related Articles: Calcium and Alkalinity Explained, Calcium, Biominerals, The Use of Kalkwasser by Russell Schultz, Calcium Reactors, Marine Maintenance, Marine Water Quality, Magnesium in Seawater, Strontium in Seawater, pH, Alkalinity, Marine AlkalinityLive Sand, Marine SubstratesReef Systems, Refugiums

Related FAQs: Ca/Alk 2, Ca/Alk 3, & FAQs on: The Science of Calcium & Alkalinity, Importance, Measure, Sources, Use of AdditivesTroubleshooting/Fixing, Products, & Calcium, FAQs 2, Calcium FAQs 3, Calcium FAQs 4, Calcium Reactors, pH, Alkalinity, Marine Alkalinity, Marine Alkalinity 2, Marine Alkalinity 3 Marine Supplements 1,

Many marines get a good part of their biomineral and alkalinity through feeding.

- Ca & Alk, Calcium Reactor - Hello again and thanks for all the past help. My system has been running at pH 8.2, Ca 320ppm and Alk 10-11dKH since installing calcium reactor three months ago. I have tried to increase Ca by increasing bubble count to 120/min (started at 60) while keeping flow constant at manufacture's recommended starting point of 2-3l/hr. Effluent is close to ph 6.5 and 40 dKH. Trend seems to be that as I increase bubble count, alk increases but not Ca. I understand that Ca is necessarily lower when alk is high. Is this just a function of reactor media (ARM) and will I have to supplement Ca or will I eventually be able to dial in Ca to 350-400ppm with the right combination of CO2 and flow. <Well, two things come to mind - first, the ARM media is notoriously impure, which means you really can't rely on it for consistent results. Second, calcium reactors are 'really' alkalinity reactors, and by boosting alkalinity promote better availability of calcium - of course it helps that the effluent is calcium carbonate, but really, I don't see anything wrong with those numbers. Do also use the growth of your calcium consuming organisms as a guide.> Perhaps I need different media (suggestions?), <Knop Korallith.> or is 320ppm & 11dKH just fine and I should leave it alone? <Yes to that as well.> A. yongei frag is doing well so far but want to get everything right before starting to stock in earnest. Regards, George. <Cheers, J -- >

Calcium and Alkalinity sagas 10/6/03 Hello, <hello again> I am in the final stages of setting up my reef system and prop tanks. <Okey-dokey> My question is that I will be maintaining alk/calcium via a Nielsen type system, and was wondering if the Kalk slurry method (Calfo) can also be incorporated to give a boost when needed...in addition to the Nielsen maintenance so to speak. <yes> Having said this, how does one typically incorporate the use of calcium polygluconate as well. <treat is simply as a superfluous supplement for stimulating coralline algae growth and nothing more> I would like to use this product for its effect on coralline.... yet does it effect alk? <no> do you use it reach elevated levels of calcium? <nope> For example can you over shoot the calcium levels past the 400-450ppm range in order to get nice rich coralline... since it does not effect alk? <no need to do so... stable Ca levels are far more important than unrealistically high levels (over 400 ppm)> Or do you use it to simply reach the upper end of the allowable stage. Confused? <regarding where to be on ranges... please read or re-read my article on wetwebmedia.com titled "Understanding Calcium and Alkalinity"> For example lets ay ?/alk are at the upper acceptable ranges... can you still add the gluconate to go further, or do you still stay within the typical ranges. <please stay low/safe> Do all test kits read or recognize the gluconate as actual available calc levels or is it some other derivative not related. <not all read/recognize it accurately. Anthony>

Calcium and Alkalinity 10/6/03 Ok Ok Calc/alk question again. <OK> 1) Does Kalk help to raise alk or just maintain it while increasing calc. <the latter... but very well> 2) Same question yet applying to calcium reactor. <raises Alk indeed... but lacks many Kalkwasser benefits> 3) How and when would one use polygluconate calcium in conjunction with Kalk...as my plan is to use a Nielsen reactor along with polygluconate for favorable coralline growth. thank you <do not rely on sugar based calcium for stony coral growth... simply add it to your present Ca dosing regime and employ it short term (less than 6 months IMO) for the support of growing corallines. Best regards, Anthony> - Alkalinity Madness, Follow-up - Well, here is the FAQ - "Alk/Calcium Hi gang, hope everything is groovy. My alkalinity reading is 60 mg/l (I'm using a Hagen test kit). Does that mean ppm? What is the conversion equation for dKH or meg/l? (sorry, I've never tested Alk in the past).  Also I can't seem to get a reading on my Calcium (readings are indicating sky high, which is improbable) as I use a Hagen test kit for that also. Is there a better/best kit? Thanks, you guys rock..  Justaguy < Hey Justaguy!  Craig here, and feelin' groovy.  The equivalents between measurements is as follows: 1mg/L = 0.02meq/L  Americans measure alkalinity in meq/L  The German hardness scale is dKH. So, at 60mg/L X 0.02 = 1.2meq/L. so using the measurement you got from the Hagen kit your alk is 1.2meq/L VERY LOW.  Most keep calcium around 425-475 calcium and Alk at 3.5 to 5 meq/L (1mg/L=0.02meq/L). Also test pH regularly as well.  I suggest purchasing quality test kits to ensure accuracy.  Salifert and Seachem are two excellent brands.  Have Fun!  Craig>" So, again, following these guidelines, my alk. would be 3meq/L, is this right? <It was my understanding that your test kit was measuring KH [carbonate hardness] which is 1:1 to dKH [German carbonate hardness]... does your kit measure in some other unit?> There is a difference between meg/L and mg/L right? <Yes.> How are you getting 54ish?? <By converting from 150 KH.> What is the correct formula. <Not sure - I use an online calculator because I just don't have time to do anything else: http://www.saltyzoo.com/SaltyCalcs/AlkConv.php> How could I possible have 54ish? <Again, was working on the information you provided which said "I dropped 15 drops to color change.  Kit says, to get KH, multiply number of drops by 10." - that's KH, same as dKH which is what I plugged into the calculator - I could have misunderstood, it wouldn't be the first time.> Thanks crew!  Micah <Cheers, J -- >

- Shaken not Stirred - Hello folks! I love your site (best on the web) and really hope I didn't just miss the answer to these questions somewhere in the faq's. Hopefully you can help me out here. I was reading Anthony's article on calcium, in specific, the section pertaining to different sorts of supplements. He seems to be advising against using liquid calcium supplements due to a sort of ionic imbalance in the long run. He seemed ok, however, with using a 2 part system. Is there a reason that this is not a problem when using a 2 part system? <They are ionically (is that a word?) balanced. One part is buffer, the other calcium.> I currently run ESV b-ionic on my 75 gal reef and do not wish to have long term problems. <ESV is a fine calcium supplement.> It has shown me stable calcium around 420 with alk at about 10. Live stock seems very healthy with everything from mushrooms, buttons, Capnella, to Montipora reproducing or growing steadily. In fact, the only thing that doesn't grow is coralline algae! <Give it time.> Other than on the rock (approximately 110 pounds) I have no calcareous (sp?) at all. I run 2 96w (blue and 10k) pc's and 2 40w zoomed Reefsun. Calcium 420, alk 10, magnesium 1300, nitrates 10-20, phosphate 0. Is the lack of phosphate the limiting factor? <I don't think so. As I said, give it time.> Thanks, JL <Cheers, J -- >

Calcium/alkalinity supplements 09/09/03 Hello crew, <Hi Marty, PF on call tonight> I am looking for some clarification on two part supplements, specifically Kent A&B. I have a 120gal reef tank with a 100lbs live rock that has been up a running for 8 months. My livestock consists of a hammer coral, candy cane, open brain, green mushrooms, green star polyps and some brown and yellow button polyps. I also have a couple of tangs, clowns, Chromis, cardinals and some shrimp. I have been adding equal parts A&B daily and maintaining a fairly good balance. (12 dKH & 350 cal).  These are currently the only supplements I am adding.  I tested the other day and noticed the calcium was starting to creep down under 300 while my alkalinity remained at 12 dKH. I know that both cal/alk can not be simultaneously high, but I would like to get the calcium back up to the 350-400 level.  In reading the FAQ's I have found that the answer to increasing the calcium is to temporarily add calcium chloride until the target value is reached then continue on with the equal parts of A&B. Is this the same as just adding more of part A, in which the main ingredient is calcium salts?  I'm assuming that this is the same as calcium chloride. I just want to make sure I am not going to screw up the of the balance if A&B are not always added in equal amounts. I know the real answer to this question is to buy a calc reactor,  hopefully I will get there in due time. Thanks a lot for your help.  Marty <I would advise you to just use the calcium chloride, "calcium salts" implies more than one kind. And you're right, the real answer is a reactor. You might also want to look into adding Kalkwasser to your daily top off. Have a good evening, PF>

- Alkalinity Test and Kalkwasser Dosing - Thank you for the prompt reply! <My pleasure.> I have an alkalinity test on order so hopefully this will provide some additional clues soon.  Actually I do have test strips that include an alkalinity test but this reading has always been off the chart (I think this particular test on my test strips is intended for freshwater only).  I quit using test strip soon after I setup my aquarium because they were too difficult to interpret and I questioned the accuracy.  <Strip tests are notoriously inaccurate.> The alkalinity test I have ordered is from SeaChem.  What is your opinion on SeaChem tests? <Should do you just fine.> My main curiosity now is regarding your original reply - you said my Kalkwasser use is not optimal.  When I said I use Kalkwasser in all of my makeup water, what I meant by this is my makeup water is made by dissolving 1 tsp of Kalk in 1 gallon of RO water, then pouring-off the clear solution into a makeup water container, from which I add approx 1 - 1.5 gals/week to my main tank.  To me this sounds like the same approach you mentioned. <Same but different... unless I misunderstood your top-off method. Typically, well at least in my tank, the top-off water sits for days and days before the container needs to be refilled. Kalkwasser won't work like this because it will settle out of solution - it needs to mixed and used within 12 hours or so.> Does my clarification help or did I misunderstand your description of optimal use of Kalk? <Perhaps we are both misunderstanding something...> I have read about adding acetic acid to the Kalkwasser mix to enable higher levels of Ca to be dissolved ( http://www.reefscapes.net/articles/breefcase/kalkwasser.html ).  Is this more of an optimal use of Kalk? <Uhh... not in my opinion. Even though acetic acid is weak, you can still do some harm to the buffers in your system, and once they are gone, they're hard to get back. Do read though our Kalkwasser FAQs, as I do believe Anthony Calfo lays out his "slurry method" which I think you will find useful. Also, here's another article for some background: http://www.wetwebmedia.com/calcalkmar.htm > Greg <Cheers, J -- >

Establishing Calcium and Alkalinity <Hello! Ryan with you today> I have a 58g reef tank that I started about  2 months ago.  I have 70lbs of live rock, 40lbs live sand, 2 clownfish, 1 Kole tang, 10 snails, and 5 crabs. <OK> I have a Euro-Reef cs6-1 skimmer, 250w 10,000k metal halide light, 450gph sump pump and 300gph circulation pump.  I've start thinking about adding calcium to my system to get ready for corals and I can't decide which method to use. <Understood> I'm thinking Kalkwasser, 2-part calcium/alkalinity, or Seachem reef advantage calcium. <B-Ionic 2-part calcium alk is what I prefer> I'm looking for least maintenance, most idiot proof, and most effective. <Exactly why I prefer it> I would also like a recommendation for inexpensive test kits for calcium and alkalinity. <Seachem works well and is reasonable> What are your thoughts on the calcium situation and what are your thoughts on my setup so far? <Sounds great, you've got sturdy equipment list and you're taking it slow.  I'd add some live rock if possible, you'll want at least 1 pound per gallon.  Best of luck! Ryan> Your help is much appreciated.  Thanks,  Chris

Ozone and Alkalinity Question - 8/10/03 Dear WWM crew, <howdy> My 240 gallon tank is currently running at 375 mv to 398 mv without my Clearwater ozone generator turned on (last several days).   <very fine> The ozone is set to turn on at 345 mv.   <And your hi-point is set for just under 400 I presume?> If I understand it from Bob's book, that over 400 mv is dangerous to the life in my tank. <rather... it's the high end of the safe zone. Agreed> My tests for alkalinity yield 14.0 dKH.  My calcium is 350.  Any advice or suggestions? <your ALK is too high... do let that stray down to a ceiling of 12dKH. The calcium is fine however. No need to fixate on specific numbers... just stay stably within a range> Current parameters: Ph ranges from 8.28 in the a.m. to 8.4 in the p.m. Calcium Reactor effluent Ph is 6.78 Ammonia=0 Nitrites=0 Nitrates=25 Salinity=1.026 Temperature=80 (temperature is controlled) 300 lbs live rock in display, small amount of live rock in refugium.  Live rock teaming with copepods and amphipods. Several white Syconoid sponges present on the rock. Small amount of coral gravel (1 to 2") in display and refugium. Good amount of macro algae in refugium. (Light on 24/7) <all fine> Fish=Picasso trigger (In sump waiting for a home), blue tang, 3 yellow tangs,6 blue/green Chromis, 6 line wrasse, watchman goby, green mandarin and scooter blenny. Corals=torch coral, brain coral, cabbage coral, colt coral, Kenya tree coral, button polyps. Inverts=Crocea clam, bubble tip anemone, cleaner shrimp, coral banded shrimp, tube anemone (in refugium), several hermits and a few snails. <dreadful to see the anemone mixed in with sessile cnidarians/corals... do reconsider removing to a species tank or ancillary tank at least (very risky long-term as a motile cnidarians... unnatural too)> Additional equipment=Acrylic tank with corner overflows, 3-175 w 10k M.H. w 2 - 95w blue actinic VHO's, CS8-4 Euro reef skimmer, 4 maxi jet 1200 powerheads in display tank and 2 Mag 1200 return pumps. <you have a fine system overall... no worries. Best regards, Anthony>

- Calcium Question - Hi, <Hello, JasonC here...> I realize you guys are inundated with questions regarding calcium and alkalinity, but I've decided to add a few more if you don't mind.  I've got a 30 g reef tank moderately stocked with many types of mushroom corals, polyps, a leather and colt coral, and Xenia. Recently I've been trying to raise calcium levels b/c after testing w/ a kit I found they were about 260 mg/L.  I've been adding b-ionic, Kalkwasser and also SeaChem reef calcium.  With all these additions, the calcium levels don't raise much but I've found my alkalinity went to the top of the chart (Salifert test) and this goes back to normal levels after about 2 days.  My coralline algae on the back of the tank has started turning a bright pink color and is spreading all over the tank, which I take as a good sign. <Indeed.> First of all, is it normal for the alkalinity to spike so high yet the calcium levels don't change? <Not necessarily 'normal' but is predictable.> The polyps retract (including the Xenia) when I add these supplements and after a few hours they come back out. <You are probably adding too much at one time... should meter out over the course of the day.> What would you recommend to bring the calcium levels to where they should be? <Depends on the makeup of your system. If I were to just hazard a guess, I'd bet you don't have a lot of substrate or live rock - natural sources of alkaline reserve.> Should this be spaced out over days or done at once? <Always best to make additions/changes slowly.> Finally, I notice the tank does much better when I do a water change (about 5 g ever 2 wks) then with any supplement I put in the tank.  Is this always the case? <Not always... but seems to be in your instance.> Or can one figure out a supplement regiment that has the same effect? <Sure, but I'd be looking to stabilize the alkalinity first... calcium will fall into line after that. Please read here: http://www.wetwebmedia.com/calcalkmar.htm > Thanks for your help, Ben <Cheers, J -- >

Water parameter problems 6/20/03 I have a 6 month old 120 gallon tank with 30 gallon sump.  My water ph and ca stay low constantly - 8.01/350 respectively. While my alk is sky high 13.4 dKH.   <the ALK is high... getting a bit dangerous in fact and directly related to why your Ca is low. Read more here: http://www.wetwebmedia.com/calcalkmar.htm> Other parameters as follows water temp 80, phosphate .4,Nitrite 0, Nitrate 0,ammonia 0, sg 1.022.  I have 2 clowns and a flame angel, and several soft corals.  I have been using a 2 part ca additive regularly (Calxmax).   <hmmm... if using the two part product and still with an imbalance, it tells us one of two things: 1) you started dosing the tank without adjusting the water first (2 parts only carry on balanced supplementation of a balanced aquarium... cannot magically correct an imbalance), or 2) dosing of the supplements has been done without vigorously mixing/shaking the products with every use... they settle by density in the bottle and can skew your chemistry is dosed this way> Thanks for any suggestions. Kevin <do read in our archives too (google search from WWM home page) about opening a window and aerating the tank to take care of depressed pH. Very common. Best regards, Anthony>

Calcium and alk stuff! Hello crew! Thank you in advance for your help! You have helped setup my reef tank over the last year and now it is quite nice! Your help has been invaluable. I had let my reef tank go several months without checking the Calcium or alkalinity. <Shame, shame, shame.> When I first checked it last week, it was at nearly 700 ppm Calcium, an alkalinity of 1.8 meq/L, and a pH of 7.9. <Ew> This occurred because I was using a SeaChem's line of reef additive without testing the results. I never added a buffer solution! <Yep> My first corrective action was to buy Kent's buffer solution and raise the alkalinity to 4.0 meq/L. I also started using your "Lime Slurry" method. I started adding ? of a teaspoon to 16 oz of pure RO water and then added this to my tank in the AM before lights on. I increased this daily while checking the pH with a digital pH probe. Now I am adding 1 teaspoon the same way and my pH only increased this morning from 7.95 to 8.06. Also this morning my calcium was down to 595 ppm and my alkalinity is 4.0 meq/L. <Sounds good to me, although the calcium seems abnormally high for that alk level> Adding 1 teaspoon a day is raising my pH slowly and I will continue until I reach a peak pH (just before lights out) of 8.35. <Why? Your calcium and alk levels are already very high. Don't be so concerned with the pH number, it's more important that it isn't swinging all over the place. During the day, my pH hovers around 8.0, it's very common.> At that time I will stop adding everything and determine my daily Calcium usage just like I read on the WWM website! I use SeaChem's test kits and receive very consistent results. My source for the Calcium Hydroxide is Ball's "pickling lime". I read on WWM site that you CAN and CAN NOT use baking soda (Sodium Bicarbonate) to buffer the water. Can you explain when it is acceptable and when it is not acceptable to use it? <See below> Can you also explain the best method for adding it? <Dissolve in purified water then pour in sump (if you don't have a sump, dissolve it good and slowly pour it into an area of high flow)> What I read on WWM was that there would be an ionic mis-balance caused by using baking soda. What is that about? <Here's an little blurb from http://www.wetwebmedia.com/alkalinity.htm "Baking soda, sodium bicarbonate, is a significant portion of most dry mixes of sea buffer. I do not recommend using sodium bicarbonate alone for most aquarists, especially new and less experienced individuals, without the strong admonition that it can raise pH quickly and dangerously without due caution. Baking soda should only be used in small portions when water quality can be tested frequently." I'm not sure about it creating any sort of an ionic mis-balance, but it is very commonly used with great success. > I am a chemical engineer and have a decent understanding of a reef's chemistry and I need more explanation before I can accept this statement. I only used the Kent buffer because I had a gross alkalinity mis-balance and did not want to take any chances while correcting it. Now that I am at a stable point I want to start using baking soda to buffer my reef. <A better way to do this is to pick up a balanced calcium and alk supplement (such as ESV's b-ionic, Kent's Tech CB, Two little fishies C-Balance, etc). Otherwise you'll be going back and forth trying to balance these levels.> What is the affect of Boron when buffering? <You don't have to go out of your way to add it, there is usually an overabundance in our systems anyways.> biweekly water changes keep enough Boron in the system to prevent this "ionic mis-balance"? <You got it> I plan on adding the Sodium Bicarbonate in my automatic top water system. Do you see a problem with this? <Nope, but why don't you use the Kalkwasser in it instead?> Do you have a suggestion for determining the right amount of Sodium Bicarbonate to add? <Randy Holmes-Farley wrote an excellent article about this and other stuff in Advanced Aquarist: http://www.advancedaquarist.com/issues/nov2002/chem.htm You'll find how much to add in that article. -Kevin> Thank you and happy reef watching!  Jeff

Kalk Slurry question- 6/4/03 Hello Folks, this question is for Anthony if possible.  I am using his "Kalk slurry" method of adding calcium.  It is a 90G tank with a 4 -5 DSB and 90lbs. of live rock.  It is a very new tank, only a month or so old, but with a mix of existing rock from a 5+ year old tank, it cycled quickly.  Right now it only has live rock in it, nothing else.  I add 3/4 of a teaspoon of Kalk in a cup of cold RO water and stir it up and pour it in, takes about a minute.  This is done about 7 am.  It takes the PH from 8.2 to 8.4.  Lights come on around 3:00 pm.  Now if I needed to add more Kalk, could I?   <you can indeed (several daily in high demand tanks... aged and mature with fast coral growth). But in this case... it is doubtful if you even need the 3/4 teaspoon daily. Check the accuracy of your test kit if it says otherwise.> The PH is at 8.4 when the lights are on, so I can't imagine I should dose more, <agreed> but the calcium level is doesn't want to go above 320, with a KH of 11.   <ahhh...there's your problem, bud. High alk and high Ca are very difficult , if even natural, to maintain concurrently. Read here and all will be revealed <G>: http://www.wetwebmedia.com/calcalkmar.htm > I use Instant Ocean salt.  I have the same problem in my older tank and I had tested the Magnesium levels in that one, they are about 3x the calcium level.  What else can I do?   <the problem is the ALK, my friend. Let it stray down towards 8 or 9 dKH and you will then see you Ca rise without changing a thing. As it is now, you are just precipitating it> I don't want to drip and I can't afford a Calcium Reactor right now.  Your help would be greatly appreciated. <no worries... heed the "marble analogy" in the article/link above. Best regards, Anthony>

2 Part Supplements Which 2 part supplement do you recommend for adding Calcium and Buffer (Kent  Tech CB, C Balance, etc.) <I always used b-ionic by ESV. They're all really the same thing and you'll be satisfied with any one you get.> I have a 125 gallon reef with fish and hard corals (torch, hammer, frogspawn, xenia). <Cool, just make sure that you pick up carbonate hardness and calcium test kits.> Thanks, <Enjoy! -Kevin> Steve

- Calcium & Alkalinity - Hey Steven Pro <Hello, JasonC here today...> I try and not ask to many question or take you guys for granted. But sometimes I just need a little clearing of the facts. And I did check your FAQs. <Ok.> Can you explain the calcium/alkalinity relationship? <Not very well in a brief email... the quick answer is that at high levels, they are mutually exclusive.> I don't mean the whole thing. I don't need numbers or specs or formulas. Just why does it seem alkalinity goes down when calcium goes up? <Uhh... you've asked the loaded question to which there is no simple answer.> Although I don't think it really does go down. There must be some symbiotic relationship. <They are not symbiotic.><<Are more "antagonistic", mutually-exclusive... though both necessary. RMF>> I just seem to be missing a piece in the puzzle. <Please read here: http://www.wetwebmedia.com/calcalkmar.htm > Thanks, Bill <Cheers, J -- >

Calcium dosing and vacations 5/26/03 Bob (or Anthony), <Howdy> I am now adding Kalk slurry in a cup of cold water after my nightly top off.  Is it okay to use Amquel-treated water, or should I just use cold tap water for this purpose?   <plain tap water is fine... distilled or DI even better> I'll admit that I started very conservatively because I hadn't gotten my pH meter yet.   <do be careful> I now have it, but with no manual, so I am waiting on some answers from Milwaukee prior to using it.   <actually... you can use it now... for the Kalk slurry, you simply add no more than will change the pH by more than .1 to .2 (within an hour or so). Calibrated or no, the meter will tell you this and you can employ it to keep up with the daily loss/drop in the meantime. You just will not know how low you are and where you need to go on the digital scale (still... use your liquid reagents for a ballpark)> For example, I don't know how often to calibrate, recalibrate, or even if I need to calibrate it prior to the first use. <a few times yearly would be nice> When I make up my saltwater for aging, I have been adding Amquel to the barrel.  Should I hold off on that and add it to the buckets I haul the water in as I get ready for the actual change?  Or does it really matter? <if you must use it (Chloramine in the tap water?), then it should be used first on raw tap water> As you recall, my saltwater showed large pH swings when exposed to an airstone (it was low and then swung up about .9 after aeration).  Does this mean anything like that I need to buffer the water?   <hmmm... the question needs to address Alkalinity (hardness) and pH... check your alkalinity to see if you need buffer, my friend> This is all confusing to me because the water shows a decent alkalinity of about 3 or 4 meq/l out of the tap. <Doh! sorry <G>... I should have read further. Ahhh... no worries. A fine ALK level. Your pH issue is related to CO2/carbonic acid more likely. Simply aerate heavily> Also, I am set to go on a few mini-vacations and one 1 week vacation this summer.  Can I leave off the daily Kalk dosing and just pick up where I left off when I return?   <usually yes.... it will fall slowly down... and be sure to bring it back up slowly and all will be fine> I am worried that the slurry method is to prone to misuse by a house sitter.   <very much agreed> I do have some Kent Tech CB 2 part additive.  Is this a safer bet for the sitter?   <yes... very much so.> I know that both parts have to be dosed separately.   <correct> Silly question maybe, but how long do you wait between dosing each part? <Day/night would be nice... but in this case, why don't you have the sitter dose each part on alternating days (set them aside in medicine cups and mark them by day so that there is no confusion)> Also, can I use the Tech CB to raise the Ca to begin with? <yep> My Ca is now about 385 and alk is 3 meq/L.   <both numbers are fine and balanced. No need to struggle to reach some ideal extreme end of the scale. Stability at these numbers would keep a healthy tank> I've only been dosing Kalk for 1/2 week.  I am worried that I should be rigging up a semi-auto top-off system with Kalkwasser for the vacation.   <too easy to foul up... skip it IMO> I would do this with a two gallon container with airline and a pinch valve sitting over the sump. My tank loses about 1 quart/day to evaporation. <calculate the loss in advance and simply have the sitter dose measured FW only. No new/complicated drip systems for safety> My display tank is 35 gallons, with about 15 gallons additional in the back of the tank sump, 5 gallons of which is Caulerpa algae refugium.  I have no corals, but want to promote healthy coralline (I have quite a bit).  Oh, I am also adding iron/manganese dosing for the sake of the macroalgae. Thanks, Linda Swenberg <all good, my friend. Best regards, Anthony>

Water Chemistry: Alk and pH 5/23/03 hi Anthony I need some advise on this  I started to use reef advance and reef builder  for one week then I tested ph, ca, alk, this is results ph 9.0, ca 440ppm, alk 5.03, so I think ph and alkalinity are way too high. It has been one month and a half and thinks do not go down what can I do to lower alk  I thank you again Genaro <agreed... please do at least 2 large water changes (30-50%) in the next 7-10 days to dilute the skewed water chemistry. Then resume a more sensitive schedule of supplementation (smaller doses and tested more often). Do read here if you haven't yet: http://www.wetwebmedia.com/calcalkmar.htm best regards, Anthony>

Raising Calcium and pH 5/22/03 Hello again, I'm not sure how to tell who is responding to the emails today. <Anthony at bat> I have a 75 gallon reef tank with 20 gallon sump, about 90 lbs of live rock and 270lbs of Southdown sand. Nitrite is 0, Ammonia is 0, Nitrate is about 5, hardness is 9dkh, Calcium is about 330, ph is about 8.1, specific gravity it 1.024. <your calcium and pH levels are flat/low... do increase water changes, buffer and testing... some more Kalkwasser likely> I need to get my Calcium and ph up but have been conservative with adding Kalkwasser, about 1/4 tsp per night mixed in freshwater and poured into a high flow area. <Doh! answering mail too fast today <G>. Yes, agreed. Do a keyword search of our archives with the google.com tool on the home page for "Kalkwasser slurry excerpt". On one of the FAQ pages, I excerpted this dosing strategy from my book. Helpful perhaps here> I have a bubble coral, leather, green star polyps and a yellow cup Turbinaria. Also two fanworms, a yellow tang and various snails and hermit crabs. The current problem is that the yellow cup coral had a small section of die off on one edge when I purchased it and it now seems to be spreading. I am feeding the cup and bubble nightly with whole Mysis shrimp do I need to try and feed each polyp of the cup? <helpful but not necessary... smaller foods though needed here> Would whole Mysis shrimp be too large for this coral and I should blend it instead? <yes, my friend> The bubble seems to be doing fine. <agreed... a large, hungry and easy feeder> I have the cup coral high up in the tank and in a high flow area (laminar unfortunately) I'll be getting a couple of PowerSweep powerheads to try and break up the laminar flow. <critical yes... laminar flow can literally denude the flesh off of some corals> Can you suggest anything to try and recover the yellow cup coral? <more appropriate water flow, continued good feeding and water quality to compliment time/patience> The guy at the LFS recommended breaking it off and gluing the broken edges to seal them. <not necessary or recommended. The coral can/will reclaim that part of the corallum> I really don't want to do this and would prefer to help it recover. I am going to increase the Kalkwasser addition but don't want to make a mess of things. <understood... simply test for pH in close concert (never add more than will raise your pH by .1-.2)> I have Caulerpa growing in the sump and know that I have to trim it before it completes a full life-cycle can you let me know how long this usually is? <never trim or cut Caulerpa, bud... simply thin out fronds (remove whole strands). Cutting cause the leaching or sapping of the cell. The life cycle for these algae is typically 3-6 months. If you thin aggressively every 2 months or less... you will likely be safe from events of them going vegetative> I think my next purchase will be some mushroom corals or elegance. Thanks for the help <best regards, Anthony>

Interesting pH question Bob, <Anthony Calfo in his stead. Bob travels to Hawaii this month, my friend> I almost had a fish holocaust yesterday caused by a dead Halimeda polluting my tank.   <quite possibly a vegetative act of sexual reproduction like we experience with Caulerpa (the Halimeda looked bleached and speckled afterwards yes?). This is caused by not pruning the colony adequately/often enough (allowing it to complete a life cycle) ... and/or... not doing adequate water changes and/or supplementation of biominerals (Calcium/Alkalinity) to keep up with the demand of a growing colony. Heed these needs and you can easily enjoy such algae in the future> Water turned green and cloudy and anemone turned stringy.  Fish not happy!  I removed the offender and did a massive (30%) water change and waited to hope things cleared up.  I have a refugium algae filter and live rock as my main filtering mechanisms.  Everything is clear and the fish and anemone are looking really good this morning.  Phew! <very good to hear. Water changes are life savers <G>> I have always had low ph (7.9 measured in the AM).  My hardness runs around 3-4 meq/L.   <the pH is indeed low, but the ALK is fine> Calcium before the incident was 380.   <no problem... a whisker flat. If the dosing of such minerals is inconsistent though to get these averages... that would be part of the calcareous algae problem (dosing small amounts of Calcium daily, yes?)> The Halimeda was new and the water parameters are not terrible for it, so it was probably just not a healthy specimen.   <more likely stress induced if not a lack of pruning. If not the above, then perhaps the addition of a few gallons of freshwater for evap top-off in the tank recently causing a saline differential suddenly> There is another Halimeda from the same shipment that is vibrant green--another verification of the water quality. <not a fair indicator... different stages of life cycle possible here> Anyhow, I would like the ph higher for my sanity.   <agreed> I have a nice coral substrate, but getting old.   <over 18-24 months needs some exchanging/refreshing> So I started replenishing it with new aragonite sand about a month ago.  I thought that might help with the water parameters, but the ph is still about the same.  (As an interesting side note, I used to have ridiculously high Ca as measured by my Seachem kit.  Now I figure that was due to a not very good quality saltwater mix.  I have switched to Instant Ocean.) <very good... agreed with the move> I thought with this large water change that the ph might budge higher a little.  It didn't.  I had to make up new saltwater yesterday after doing all of these water changes.  After testing the tank ph this morning, I ran out to my garage and tested the pH of the water that has now been heating and mixing in my trusty Rubbermaid for almost 24 hours.  It measured 7.8!!  I'd like to fix the pH of my synthetic saltwater before I even think of tackling the pH in the tank. I use tap water that is pretty hard.  I fill the container, add my salt and Amquel and allow it to mix with a powerhead and heat for about a week with the lid on the barrel to prevent evaporation before using.  This lasts me several water changes usually.  I don't usually test the ph, figuring the synthetic salt should take care of this.   <agreed/largely> Could the lid on the container been preventing gas exchange, keeping the ph down? <in any vessel yes... but what of the display tanks low pH? Test any/all by aerating a glass of saltwater outside for 6-12 hours and seeing if you get any pH increase> What should be the procedure?  Should I buffer it with baking soda prior to adding the salt?   <depends on the pH/hardness of the freshwater you are using> If I keep the lid slightly open, don't I then have to worry about salinity due to evaporation? <very little concern here... do encourage good gas exchange> I don't usually do any Kalkwasser dosing or anything.  I do have a Kent 2-part calcium  buffer around when from when I first set up the refugium and the Ecosystem folks said that I might have to dose calcium with this set up.  I got it just in case, but haven't really used it. <I would strongly encourage Kalkwasser use... and strongly discourage any liquid calcium (chloride) long term usage [much info in our archives and out on the 'Net about the dangers of using liquid calcium long term... problems often after a good 8 months or more]> Thanks again for all of your help.  You have made my aquarium hobby much more enjoyable. Linda <with kind regards, Anthony>

Halimeda going vegetative and Kalkwasser 5/19/03 Anthony, Sorry to think you might be Bob.  He answered me about a monster sea cuke a few days ago (don't worry, it has found a new home...). <no worries... we all share a communal mailbox and all help as/when needed <G>> > <more likely stress induced if not a lack of pruning. If not the > above, then perhaps the addition of a few gallons of freshwater for  evap top-off in the tank recently causing a saline differential  suddenly> Bingo!!! The LFS guy told me my salinity, at 1.025, was a little high.  I have been attempting to lower it over the last few days and got it to between 1.022-1.023, but now realize that it was too fast for the tank's occupants. <Ahh, yes. A common catalyst. Have done this myself...heehee> Normally, I top-off my tank (about 45 gallons) every few days with 1 gallon of freshwater treated with Amquel.  I put the Amquel in the bucket then simply pour water from the aerating sink tap into the bucket very fast.  This is allowed to sit for at least 15 minutes and then poured directly into my pump return chamber that feeds directly into the display area of my tank. <just curiously... was the affected Halimeda near to the outlet/return? Makes matters worse/argument/diagnosis stronger> Whatever is leftover is left in the open bucket under the tank for top off another day.  I hope this works because I hate to have to add even the noise from a small air pump to my small house just to bubble the make-up water! I have no corals, but do have live rock and some inverts and macroalgae in the refugium and a few up front in the display (if they survive my abuses).  Low maintenance is really important to me, which is why I went for the algae scrubber filter to begin with. I tried to find everything about the Kalkwasser slurry from the faq's and I will go get your book and skim through that section. <do use a keyword search for "Kalkwasser slurry" on google for our website, if you haven't found the excerpt. Its on one or two of the FAQ pages> Can I modify my top-off regimen by mixing up the Kalkwasser in the 1 gallon bucket to create the slurry and then pouring in to top-off at night after the lights are out every night?   <not really... a slurry is made in a small glass of cold/cool water and shot in immediately... no Kalk (slurry or super saturated solution) can be left exposed to air (as in open bucket) as it forms insoluble calcium carbonate (the chalky sheen on the surface of the water) and wastes Kalk> Do I need a digital pH meter or will an accurate testing kit suffice (I have the Seachem Multitest)?   <a digital meter will be highly recommended if doing the slurry method... else simply use Kalk in a slow drip of supersaturated solution. That will likely be fine in your case here with a lower demand in the tank for calcium (sans corals)> How long do I wait to check the pH change for each slurry addition?  If I haven't been dosing calcium up until now, how do I know what the daily Ca dose should be for a healthy tank, knowing that I also am trying to get the pH up (recall it is around 7.9 currently). <all explained at length in the archives my friend... my apologies for the redirect, my friend... but we struggle to deal with the volume of mail we get every day and must rely on our archives rather than rewrite popular topics over> What is the best way to raise the pH in a Rubbermaid barrel full of low pH saltwater mix?  I left the power head on all day with the lid off and it is still just as low.  Can/should I just use baking soda?   <baking soda (small amounts slowly) is usually all one needs... Kalk helps afterwards in the tank> I thought Instant Ocean has buffers to equalize things?   <sort of... but you/we must understand that the formula is fixed, our source waters among users across the world (and even seasonally with a single user) varies widely. We must be realistic and make adjustments for our individual needs in some cases based on this> All the water has in it now is Amquel and IO mix... Linda <have you read this article yet, my friend: http://www.wetwebmedia.com/calcalkmar.htm perhaps a good primer. Kind regards, Anthony>

- Ca/dKH Questions - Dear WWW Crew, <Greetings, JasonC here...> Thanks for your advice in the past and the great web site. I have looked through all of the calcium FAQ's and am unsure how to proceed with my own reef. I have a 4 year old 75 gal reef with 80lb live rock and a 30 gal refugium with a 7 in DSB. I have several LPS corals and a variety of soft corals with a few small fish. The corals are doing very well (I've divided my frog spawn several times). I have a Turboflotor 1000 skimmer and a Korallin calcium reactor. I do 5 gal water changes monthly and top up water with a "NURCE" device using buffered R/O water. My chemistries are pH 8.3 (day)/ 8.0 (night), dKH 9.0, Ca 400, Mg 1300, nitrite/ammonia/nitrate 0. Since getting the Ca reactor the Ca/dKH have been much more stable (compared to chasing levels with supplements alone) but NOT optimal-Ca 325 and dKH 8. To boost this up I use Kent Super buffer 4 tsp. every 4 days and add Kent turbo Ca to the make up water (~3/4 tsp. per day). I have tried Kalkwasser repeatedly in the past with unimpressive results. In addition I frequently work over night and cannot dose stuff when the lights go out very often. This winter I tried 3 months of Warner's 2 part buffer and had o.k. results (Ca 400, dKH 8.5) but needed to use maximum amounts (estimated to cost >$300/year). I am concerned about my calcium and alkalinity supplementation. I have noticed some bad mouthing of the Kent products in the FAQs...any specific problems? <Well, in most cases they are the great imitators... copied products from other companies that did the actually research.> Will this amount of Turbo Calcium cause an ionic imbalance and how do I recognize the symptoms? <One or the other [ph/dKH] will be very high, much higher than they are now.> What Ca reactor media do you like the best? <Knop Korallith.> How would you recommend I proceed? <I would consider two things... first, unless you've done this already, you should replace at least half of your live rock and sand bed. This is a process that should be done once a year in smaller percentages, but I get the feeling you've never done this... your alkaline reserve is really embodied in your sand bed and live rock, and over time it gets used up. Adding supplements is only useful to the point that they actually have a place to go. Also, if you don't run your refugium this way, pack it with macro-algae and light it during times when the tank is dark - this would help keep your pH a little higher and also allow you to turn up the calcium reactor a little bit. Do start with swapping out some rock and sand - this is the best place to start.> Thank you for your response...you guys do a great job! Sean <Cheers, J -- >

Smooth sailing on Ca & ALK? 5/5/03 What is your take on this?  For months I used two part b-ionic with good success in my 29 gallon reef tank.  (Prior to that, for a couple of years, I tried the balancing act of adding calcium and buffer separately.)  Anyway, out of the clear blue sky, I have found the calcium and PH levels staying extremely stable and I have stopped adding the bionic.  (Will continue to monitor of course.) <Hmmm... you haven't mentioned you ALK (hardness dKH) and I wonder if your test kits are accurate (over 6 months old for reagents?). Before you stop any crucial supplementation... please confirm you water quality on other test kits for reference> The tank is skimmed, strong circulation, constant small water changes, live rock/sand and the best husbandry possible. (Bordering on obsessive.)  No supplemental additives. only corals are corallimorphs, no algae. light fish load,  no problems whatsoever. Could this be the reasons the tank stabilized? <perhaps... simply a low demand/bio-load> Thanks for the input. William <best regards, Anthony>

Dynamic Dynamics of the Calcium Alkalinity Dynamic Hey guy..    hope this question finds you all doing well. <Just dodged a round of layoffs at work, can't complain.  Maybe it's time to move on.> I found  a site stating that the balance to an Alk level of 4 meq would be 440 ppm Ca . Does this sound ok with you enlightened folks.. <My search for enlightenment, hmm... I do need to get back to that, but for now lets talk Calcium and Alkalinity.  4meq Alk is a fine hardness, when your Ca gets up around 440ppm you will want to watch for creeping and spikes, 440ppm is towards the top of the scale too much higher could cause precipitating Alk.>  Rush is talking about you guys when he says "Knowledge on loan from God" hehe .. <Ha, simpler than that, people sharing is a good thing.  Check out the following link for a good article on the relationship between Calcium and Alkalinity. -Gage    http://www.wetwebmedia.com/calcalkmar.htm >   keep up the good work. <Will Do.>   Mike

- Low Calcium Redux - Jason, many thanks! <My pleasure.> A final point: You suggested, <<I'm not real familiar with the Tropic Marin Bio-Calcium, but I'm pretty sure it's calcium carbonate along with a bunch of other stuff... quite likely that this is what has your alkalinity where it is now.>> Yes, that could be it...or, it could be all the buffer I've been adding: Kent's Superbuffer - dKH. <Ahh... you left that detail out before, that would also bring up the alkalinity.> I have been adding 1 1/2 scoops every other day. I think it wise to cut way back on the buffer additive for now, and take readings to make sure the dKH doesn't drop too far.  Make sense? <Yes, good plan.> Thanks again, Jason. Best, Ralph <Cheers, J -- >

- Ca KH difficulty - Hello all, I hope all is well. <And hello to you, JasonC here...> My question is in regard to my difficulty maintaining alkalinity and calcium levels.  My readings are as follows: Alk 11 deg, Ca 340, pH via pinpoint 7.90 prior to lights on 8.2 just prior to lights off, 0 ammonia, <10 nitrate.  In a 75 gal tank + 5 in the sump I do 6 gal weekly water changes with buffered aged DI prepared water (pH 8.3, 13 kH).  The only stony I have is an E. divisa, and I maintain a medium sized crop of Hailmeda (growing like crazy, using significant Ca) along with 90lbs nicely covered live rock, star and button polyps and some mushrooms.  I am trying to maintain pH above 8.3 (I want to utilize a Xenia scrubber), Ca around 400 and KH of 13.  In order to keep the measurements I have, I find myself needing to dose 1/4 tsp. calcium hydroxide via the slurry method, and 2 tsp. Seachem reef buffer daily (in excess of Seachem directions).  I wouldn't be so concerned except for the fluctuating and depressed pH. <I would be looking for sources... things that would lower your pH - large amounts of Halimeda could contribute via respiration over night... likewise, this could be a calcium vacuum for you, you might want to keep the stuff in check, perhaps sell/trade some back to your LFS. Also, if your house has been closed tight all winter, you might try opening a window or two and freshen the air in the house - this sometimes gives temporary help.> I monitor pH continuously and test parameters 3 times weekly. Is there something I am missing or should I continue to test/increase buffering and slurrying? <In your case, with the pH as low as it is in the morning, you could do some real harm with a sudden pH shock by adding a slurry... you might be better off slowly dripping the same slurry overnight, which would help offset the pH drop.> Thank you for all of you advise in the past. Ed in NJ <Cheers, J -- >

Learning To Dance (The Calcium/Alkalinity Dynamic) Hi, guys.  I've been trying to find information about using Kalkwasser and so far I haven't found what I've been looking for.  I have read Understanding Calcium and Alkalinity but I'm not sure if I understand. Could you direct me to the proper place on your website or provide specific information about using Kalkwasser.  I can't seem to maintain calcium and alkalinity levels at the suggested levels without buffering the alk and adding liquid calcium every 3-4 days. Richard <Well, Richard- you may want to check out this link for more information on Kalkwasser: http://www.wetwebmedia.com/kalkwasser.htm You also may want to check out Anthony's "Book of Coral Propagation" for a lot more on Kalkwasser use, alkalinity, and calcium in reef systems. Finally, you can use the Google search feature on the WWM site and do a keyword search...I'm sure that you'll find what you need here! Good luck! Regards, Scott F>

High Calcium & Alk Hello & Good Day! <Good day to you> I've read all through the Calcium and Alk FAQs and they've added to my confusion.  Here's the scenario; Tank is 75gal with 75lbs LR and DSB.  Tank completed it's cycle 10days ago.  Since then I've added 2 dozen snails and 1 dozen hermits over the course of seven days.  A few days ago I decided to start testing Calcium and Alk to see where I stood and to make sure my Coralline was going to do well. Day 1 of testing Calcium / Alk in main tank = Cal 210, Alk 11.5   So I added some Tropic Marin Bio-Calcium. "Contents are calcium ions, hydrogen carbonate and all 70 trace elements found in natural sea water." Day 2 of testing Calcium / Alk in main tank = Cal 300, Alk 13.8    tested Replacement Water ( 10gals ) = Cal 270, Alk 9.9  Added Tropic Marin to both. Day 3 ( Today ) of testing Calcium / Alk in main tank = Cal 315, Alk 15   tested Replacement Water = Cal 255, Alk 12.2 …So… I -thought- that as one raised the other would lower but it actually looks like both are rising in my main tank.  I'm adding the Tropic Marin as directed but now that my Alk is out of the recommended range I'm leery of adding anymore. <The Tropic Marin could be raising both.> What should I do?  Wait a couple days and test again?  Use a product to lower Alk?  If so, what?  I'd like to start placing some actual fish in the system but not until I can understand and handle what I've bitten off so far. Thanks for your time! Scott <I would start by doing several large water changes (25%-50%) over the next 7 to 10 days, without adding supplements.  This should dilute the imbalance.  Then resume supplementation with a 2part calcium supplement, Tropic Marin, or Kalk.  Best Regards, Gage>

- Balancing Chemical Equations - All, <Good morning, JasonC here...> When Calcium Chloride is added to water, you get wanted calcium ions and unwanted chloride ions.  Does Sodium Bicarbonate (baking soda) break up into sodium ions and bicarbonate ions? <Oh man... general chemistry seems so far away right now. I think for the basics, yes this is true.> If so, wouldn't the chloride ions combine with the sodium ions to form NaCl, salt?  It probably isn't a perfectly balanced equation, but it seems that it could mitigate the usefulness of calcium chloride. <It would seem that way, but there are other reactions taking place in a marine system that would also need to be taken into account. What those reactions are exactly is escaping me at the moment... but on the simple path, I think this is true - you would produce salt.> If each is added in *small* quantities, say Calcium Chloride in the early a.m. and Sodium Bicarbonate in the early p.m., couldn't they become a useful adjunct to regular Kalkwasser use, if Kalkwasser alone was not supplying enough calcium to meet the daily demands of a given system (as is my case). <Well... if you look at a bottle of ESV B-Ionic, you will find that their part A is calcium chloride, and part B is sodium bicarbonate, and part B buffers part A. So in effect, this is similar to the reaction you describe. I'm not a huge fan of Kalkwasser myself - much to easy to get into bad trouble with. You might want to consider a calcium reactor - the cash outlay is perhaps a little high up front, but in the long term will save you money, grief, and is much better for your system than calcium chloride.> Thanks in advance. Sincerely, Mark Schwartz <Cheers, J -- >

Striking A Balance Hi, <Hello- Scott F with you!> I just have a quick question. Can alkalinity ever be too high ? I tested my calcium level and right now it is about 350 (test only measures in increments of 50). I was told by my local fish store that if my calcium is only 350 then alk can never be too high and that if I added buffer every day it would be fine? Does this make sense. How often should I add buffer? <Well, any substance that you add to the water, including buffers and Kalkwasser, requires testing to verify not only that the amount that you are adding is appropriate- but to see if it is even necessary. Just adding buffer or other additives without supporting water testing is a bad "habit" to get in to, IMO!> They told me to put in every day to maintain current level . This does not seem to be correct in my opinion. I was under the impression that if I dosed Kalk, this would maintain alk, and that the higher your alk is the lower calcium will be. Thanks <Well, your LFS seems to have made a very generalized statement. The calcium/alkalinity dynamic is somewhat confusing and often misunderstood. Suffice it to say (and here I am generalizing!) that a very high calcium level often has an accompanying moderate alkalinity level. You really cannot have both high calcium and high alkalinity at the same time...As Anthony eloquently points o ut with his "marble analogy" in his "Book of Coral Propagation", a given quantity of water can only "hold" so much, before something has to "fall out" of solution. The best thing that we can do is keep a "balance" between the two factors. Remember, too, that we tend to get really fixated on specific readings as our "target", and sometimes forget to just look at the aquarium...Your animals will let you know if your calcium level is sufficient, through growth and overall health. Do a little reading on the WWM site to get a better understanding of the calcium/alkalinity dynamic...You've got a good idea so far- just keep reading up on it! Good luck! Scott F>

- Stabilizing Calcium/Alkalinity - Thanks for the reply. <My pleasure.> I apologize for the many questions that follow. <I'll get over it.> Yes I have read the article on "Understanding Calcium & Alkalinity" and there was some confusion. I have noticed many aquarists stating on their websites too have both very high calcium levels as well as high levels of alk in their tank water. Am I right in assuming that this is an unstable situation and that this would require constant monitoring? <That is a good conclusion.> How do you get both levels so high? <Jam the stuff in there.> Because that is what I was trying to do, thinking that it is a good thing. <Yeah, many people 'think' it's good, but honestly, alkalinity and calcium are nowhere near that high in the wild - somewhere closer to the middle of the scale.> In my current tank state should I continue doing water changes until calcium levels have dropped to below 400 ppm? <400ppm isn't dangerous - in fact, that's fine.> Do I then need to test both calcium, Ph and alk, <I would...> from previous experience I assume that the alk will be low. <You are probably right.> Would I then need to raise the level of alkalinity until the system is in a balanced state? <I think you could probably raise the alkalinity without necessarily dropping calcium below 400 ppm.> i.e. both calcium & alk in the middle of the scale or alk high and calcium low or visa versa, is this correct? <Both in the middle of the scale would be best.> I understand that the level of alkalinity represent the buffering capacity of the water? And it's ability to resist changes in the PH level? <Yes - both are the same - buffering capacity is the resistance to pH changes.> Would it then not be better to keep the alk level high? <Shoot for the middle.> Calcium on the lower part of the scale? <Same here.> If so, what is needed to raise the alk level without affecting calcium and ph. <Lay off the calcium for just a little while - the chemical processes in the tank are inter-related so that some of the required calcium will come out of your substrate and live rock.> Do I need to get to a balanced state. before starting Kalkwasser or liquid supplements? <I would.> (Cannot afford a reactor now - also have mostly soft corals so demand is not that high) or will Kalkwasser or 2 part supplements do it? <Two part systems and Kalkwasser will do nothing for your alkalinity, so... I would work on that first.> Could you also venture a guess as to why the tips of the algae (Halimeda/Caulerpa) turn white/translucent, the base of the blade is a healthy green? <Could be a couple of reasons - this is typically the area where new growth occurs so that could be one explanation. Could also be due to water chemistry.> Your insights will be appreciated. Cheers Hilton <And cheers to you, J -- >

- Calcium & Alkalinity Tests - Hi Crew, <Greetings, JasonC here...> I have a question (or a few) I have had my reef tank set up for about 5 months. There has not been to much coralline algae growing in the tank. I purchased a Red Sea calcium and alkalinity test kits. Are these good kits?? <I'm not sure... I've never used them.> For the life of me I cannot determine alkalinity with this kit. It only has low, normal, and high on the side also has mill/eq. <Millilitre Equivalents [mill/eq] should be sufficient to get a reading... multiply the number you get by 2.8 and that should give you the dKH reading.> I tested my calcium with the same brand kit and it was 350. alk was somewhere between normal and high. I've added some Kent dKH buffer and over the last few days I've noticed small patches of darker purple coralline all over the glass. I am not sure when I should stop adding this Kent dKH buffer. I have been adding daily for the last four days. <What do the instructions say?> Can I assume that because coralline is appearing that the water conditions are starting to get better???? <I wouldn't jump to that conclusion myself... the conditions may have been right all along.> I also have a bottle of Kent liquid calcium can I add this to increase calcium levels or should I not. I was told by my LFS that I would be better throwing it in the trash that putting it in my tank. <I would agree... you're best bet for supplementing calcium are the two-part systems, like ESV B-Ionic.> Please excuse my ignorance I need help. <Here's your chance to educate yourself - read this article: http://www.wetwebmedia.com/calcalkmar.htm > Oh ya one more question. My Red Sea calcium test kit reads calcium in increments of 50. Directions say for every drop of reagent this counts as 50. I added 3  plus 4. which would be 7x50=350. if this only measures on increments of 50. Will it give the same reading if calcium is 310 apposed to 345. <That's a question for Red Sea... in the mean while, consider the Sera test kits as they have a much finer granularity.> thanks ??????? I need serious help. Should i stop adding these supplements? I am afraid that if I add to much and alkalinity gets to high my tank will have a snow storm. <Your numbers aren't that high, but I would for certain read that article so that you will have a better understanding of what's going on here and the relationship between calcium and alkalinity.> Thanks so much for all your help. Chris     I had to write this quick sorry for the mess <Cheers, J -- >

- Stabilizing Calcium/Alkalinity - Hi there All A question regarding my tank: Calcium levels were found to be low 280ppm, started raising it using Red Sea Reef Calcium, level went to approx 450ppm. Alkalinity was measured at the same time and found to be very low 2.0meg/l ,started raising it using Red sea reef Kalk. I seem unable to raise alkalinity any higher than it is now 2.5meg/l  and calcium levels have moved past the 500ppm mark! <Yes, well... calcium and alkalinity at high levels become mutually exclusive - meaning if one is high, the other will be low. Please read this article: http://www.wetwebmedia.com/calcalkmar.htm > I have had a very stable Ph up until now, but this has also dropped to a level of 7.9 during the day! Will be even lower at night! I have noticed the tips of the Caulerpa in the tank becoming translucent and dying off - more recently a large section of razor Caulerpa disintegrated  completely! The chemistry in my tank is obviously out of whack - could the addition of these products have started the roller-coaster ride? <Would be my first guess.> Please advise as to what can be done to stabilize things. <Stop the additions for now, do a couple of water changes, and read that article.> I have started water changes already but need a long term solution for maintaining both calcium and alk without affecting ph. I would prefer not to use Kalkwasser, a liquid supplement looks good to me. <A calcium reactor looks even better to me.> I have great difficulty obtaining most supplements in my country. Any advise would be greatly appreciated. Cheers Hilton <Cheers, J -- >

- Calcium and Buffer Additions - <Good morning, JasonC here...> Should I have to add calcium and buffer daily to keep the levels at 400ppm cal and alk at 9 or 10 even though I add Kalk slurry twice a day. <Yes.> The tank is a 125 gal reef that has been running 8 years. <You are probably due to replace some of the rock and substrate - this also give up calcium through natural processes and unless you augment it yearly, you are way overdue.> Its heavily stocked and every thing is doing well. I do a 25 gal water change every 2 weeks. It seems like the cal. and alk fall off quick. <Your buffering capacity is probably shot - again, think about replacing a goodly amount of sand.> Is this normal or is there something I can do to reduce the buffer and cal. additions. <Consider a calcium reactor - you didn't mention anything in your system that specifically requires high levels of calcium...> You have been helpful in the past and thanks in advance for your help this time <Cheers, J -- >

Alkalinity and Calcium out of what. What to supplement? This is one of the most useful sites on the net !... I have a quick update and another question… first the update… being a newbie with a reef setup… I have been reading and reading as many FAQs and messages on this site my eyes can handle during all hours of the night J … anyways I just want to say thanks for taking care of my detritus!... I started out with the snails, brittle stars, hermit crabs and a goby … all worked a little against detritus… a very little… it was everywhere..   anyways I kept reading… I noticed one strong theme (Bob)… circulation !... so off to the LFS to buy another powerhead , can't hurt right?… repositioned everything "again"… more aggressively… and what do ya ' know BINGO… clean sand!.. Thank you ! <good for you!> … now if I could just keep my yellow headed goby from sifting the sand into the current… he is making a mess on my LR… hehe … Now for my question in regards to top off water… I have been using purified tap water for now… aerating for 12+ hours, then adding buffer, then aerating again for 12+ hours more… I can't get my PH past 7.7 with the Alk all the way at 16 and my calcium only 150… I then thought the only way was Kalk , to raise PH and calcium… the PH went to 8.3 but the calcium only went to 180… how do I match my tanks parameters when the top off water is so far off??... the "water changes" are better since I get the benefits from the Instant Ocean ingredients… but since my "top off" water seems to dilute the good tank parameters… it is a progressive death… I have also been trying the Kalk slurry method early in the morning before lights on… this also doesn't seem to have much effect… I am using ? to ? teaspoon of Kalk , also adding magnesium, iodine weekly… still low PH and low calcium… I feel like I am adding way to may chemicals… the tank is 55gal, 65lb LR, and 50lb fine sand, Remora skimmer… any ideas?? <Honestly? First thing, lose the dots, very distracting to try and read. Next about your chemistry problem. See here for an explanation of what is happening: http://www.wetwebmedia.com/calcalkmar.htm. What I think you should do (as it worked for me in this situation) is this. Stop all additives. Make up a bunch of change water. Make sure the change water is well aerated and that the Alk, Calc, and pH are at the values you need (IO should give you this pretty much out of the bag). Now, do daily 5-10% water changes until the change water balances the tank water and you have the parameters where you want them in the tank. After this, do not do any supplement or water changes for 3-5 days. Measure alk/calc at the beginning of this last cycle and at the end. Subtract end from beginning values divide by the number of days and viola, you have daily needs. Dose supplements daily to replenish this need. Good Luck, Don> thanks -Brian

How Much Time Does My Tank Have? Hey there Crew, <dude...> I have a dilemma. <fess up buuuudy> According to the LaMotte calcium test, my calcium level is over 800. <how cool is that... you have a living snow globe!> My alk is 3.0 meq/l (8.4 dKH) according to Fastest kit. <the slightly low ALK is expected and necessary to prevent "snowfall" (crystalline precip of carbonates)> Ammonia=0, Nitrate<5ppm, pH ~8.2, SG = 1.025. Back in October 2002, I was using SeaTest Ca test and getting readings about 600 or so. I stopped using the two-part and did greater than 25% water changes weekly in addition to my 10% weekly water changes. I have not added any Ca additives since the end of October. <something does not add up then. Test your source water for high calcium. The Ca must be coming from somewhere. If the tap is high and you have a lot of evap, perhaps there's your ticket> I did my last 25% water change last week, and switched to LaMotte test kit for Ca this week. My current procedures don't seem to be lowering the Ca. <we simply need to ID where its coming from. Sea salt mixes up at 325-450 ppm Ca at best.> I have about 100lbs of Fiji LR, and aragonite mixed with fine sand as substrate. I have a 3 inch across brown Acropora sp., colony of yellow colonial polyps, green star polyps, metallic blue mushrooms, a bubble tip anemone, Astrea snails, 3 peppermint shrimp, and a few blue legged hermit crabs, 3 damsels, and a tomato clown all in a 55 gallon with built in corner overflow (with newly installed Durso), going into a 10 gallon sump where there sits an AquaC Urchin in the first chamber, then Chemi-pure and PolyFilter, couple of pieces of LR, and a Mag9.5 return pump. Skimmer is producing about a 1/4 cup of skimmate daily. I top off with buffered deionized water. <Hmmm... shoots that theory> My 10% weekly changes are done with aerated, buffered water made 4 days in advanced. The major 25% changes have been done with regular tap water, aerated, then buffered, then salted over 4 days. I use Instant Ocean. <yes... under 400ppm likely... Ca coming from elsewhere. Mix a batch of new saltwater and test that before it goes into the tank> However, my Acropora has started to grow (new white tips all over, and it's starting to grow over the dead skeleton base), with full polyp extension. It took many months to acclimate, I guess. My colonies of yellow polyps and green star polyps are spreading, and the coralline growth is running rampant (so many new spots growing all over rocks and glass, I can't scrape it off front pane fast enough). Snail shells are covered with coralline and I can see where new shell is calcifying(?). Help me please. Or should I ask how much time does my tank have before it crashes? Thanx, Randy M. Yniguez, MA <we should be able to control these levels simply with new seawater made with purified water. Kindly, Anthony>

How Much Time Does My Tank Have? Ca/Alk problems Thanx for the response Anthony. I shouldn't  try to raise alk level then? <nope... could be fuel for the fire> Is the tank "naturally" trying to prevent precip on its own? <sort of... or rather, high levels of both coincidently are difficult and unnatural. In a healthy tank, when one is high, the other is moderate at best. Here, though, you Ca is frightful. Dilution ASAP with confirmed low "low" (normal -350ppm) new seawater is needed> I will persist with the water changes after I test a new batch of sea water. What (side) effects could occur if I did about a 50% water change? <nothing bad with properly mixed/aerated NSW conditions> What long term effects are there if I allowed Ca to stay over 800? <hell breaking loose> Would alk start going down? <yes... very likely> Would the addition of more Ca loving organisms help alleviate or lower Ca levels? <not direct or appropriate. It assumes that they can even calcify in the skewed dynamic> Should I continue to buffer top off and water changes? <minimally and normally but not to excess> Thanx, RY <best regards, Anthony>

- A drop in the bucket - <Greetings, JasonC here...> I know, not the Alk/Ca question again. <No worries.> Have read the articles. Thanks for all your wisdom.  Here's the question.  Tank is 220g, 150g sump, 70g refugiums).   Southdown 9" DSB in Refugium, 4" DSB in Sump. ETSS skimmer, pulling like a horse.  150 lbs LR( all about 7 years old) 10% water changes every 3 weeks.  Just setup this tank after taking down a 180g.  Nitrites .001, Nitrates 2 ppm, Mag 1200, pH 8.5 day 8.3 night. Temp 78.  Now the problem children  Ca 230 Alk 5, Ouch.  Have been adding Kalk via the Slurry method.  Got an American Marine pH monitor (calibrated regularly)  never move the pH more than .1.  Been adding one tablespoon of Kalk in the morning and one at night.  Adding one tablespoon of baking soda midday. These move the pH up/down by the .1 as stated, but Ca/Alk is going nowhere.  What gives? <At the amounts you are adding, you're never going to move calcium or alkalinity in any direction. Given the fact that your system volume is over 300 gallons, you need to add much more than a tablespoon to affect a change.> As this is a new setup I don't have much in the way of corals. (2 clams, 3 small Acropora frags).  I used to control the Ca using Tropic Marin Bio-Ca, but read this was CaCl, so since this was a new setup with almost all new water thought I'd switch back to Kalk. <I would go for one of the two part systems like ESV B-Ionic or better yet...> Driving me nuts, want to add a Ca reactor, but want to get to 400 Ca 10 Alk first. <I would go directly for a calcium reactor - don't pass go, don't collect any Kalkwasser.> Any ideas? <Cheers, J -- >  

Calcium and Alkalinity I have had fish only for 3 years (40g, skimmer, Whisper hang-on power filter) and over the last month or so I've added LR and better lighting for my LR. I will keep it a FOWLR for the next couple years so you know what my requirements are - until I finish law school and hopefully start making some cash so I can move into reef (law school leaves little time or money for this hobby, but I'm trying). <Be patient, the "good stuff" will certainly come with your continued hard work!> My macro algae is dying off (I can see the crusting "shell" slowly disintegrating away) and I suspect that my calcium is low. <I assume you're talking about Halimeda or other calcareous algae> I would love for my entire tank to flourish with coralline and other encrusting macros! I will be purchasing calcium and alk test kits very soon (and I shall know for sure), but my question is about the best way to raise it safely. My ph is also a little low, about 8.1, and has been around 8.1 for the entire 3 years I've had my tank.  Since I've stuck with hardy fish only, and it's been very stable, I haven't done anything to raise it. So I was thinking Kalkwasser would be beneficial to boost calcium, raise ph, and improve skimming to boot. Do you think this would be the best thing for my system and goals, or should I go with a different calcium supplement? <Frankly, I think Kalkwasser, properly administered and monitored, will do the trick!> From reading through the site, I also understand that it is necessary to use Kalk in conjunction with bicarbonate, since calcium carbonate is what is needed by corals (or in my case encrusting macro). I don't know if I completely understand alk and carbonate (never big on science, but it is needed for this hobby and I'm trying to learn). Is the alk an indicator of the levels carbonate in the water - so if my alk readings are within the optimal ranges of 7-12 dKH, my carbonate levels are adequate? <In a very simple nutshell- yep. It's a measure of the buffering capacity of the water. There is a very important dynamic between calcium, alkalinity, and ph. You need to understand the relationship. There are a lot of good resources regarding this dynamic on the wetwebmedia.com site (and with a lot more detail and better descriptions than I can go into here). Do check them out!> If I add marine buffer (which I understand to be mostly, if not all, sodium bicarbonate) with my bi-weekly water changes, would this be sufficient for my needs? <Well, it depends on the dKH reading of your water, but this is a good practice if it' necessary> Thanks for the time.  You're always good help in a hobby where good help is hard to find. <And thank you for stopping by! Good luck! regards, Scott F>

Calcium/Alkalinity More Follow up: Let me start our with a great big "Thank You" for all the help. <Anthony Calfo with the follow up... and you are welcome, my friend> With valuable resources like this site and my "Recently Ordered" copy of CMA (can't wait to get it). There's no doubt that "this time" my tank will be a success. As a follow up to my last questions; I was (no longer) adding Sea-Lab #14 and #28 (without testing for Ca, just following directions and watching pH. I now know this was foolish of me.) and suspect this is the cause for my very high Ca and maybe my red slime out break. Along with my (Ca) test kit I have purchased the SeaChem Reef Calcium as Anthony suggested, but am waiting for Ca to return to normal levels before beginning this product. <agreed... and a second Ca test kit wouldn't be a terrible idea either for comparison> The Ca rate is dropping. From 1080 this past Sunday to 675 today. My concern is for my Domino Damsel and the dropping pH. Down to 7.7 from 8.3. <agree... dangerously low/fast> Yesterday I started adding Baking Soda to my 55g tank to attempt to stabilize the pH. I have searched the FAQ's and web, but failed to find the recommended dosage. <there is not amount per tank/gallonage as everyone DOC and acid levels vary by system. The dosage of baking soda is limited by how fast a given amount makes your pH rise. Just start slow and be sure to use no more than will raise your pH .2 in one day><<Mmm, would have suggested measuring alkalinity... using this as a basis of determining "alkaline demand". RMF>> I'm currently adding 1 1/2 tsp per day. (Based on the dosage of Part B on the Sea-Lab #14, figuring it was also baking soda) Am I on the right track here? <the amount is reasonable... but simply test your pH an hour later to verify> Thank you for helping Dave <best regards, Anthony>

High Calcium / Low Alk Hi guys, My pH is stable at 8.3, but my alkalinity is 4.5 and my calcium is over 520!   <wow... please immediately stop using additives and do several large water changes to correct the imbalance. You are in danger of a crystalline (and catastrophic) precipitation> What is the best way to remedy this situation.   <large gentle water changes> I'm currently using the EVS B-ionic system; should I just use the Alkalinity component for a few days and lay off the Calcium? <nope... the condition got this way because you either added the new 2-part to the tank when it was not balanced (you must be balanced to continue with balance)... OR... (my guess) you have been using the calcium part without shaking it vigorously before every single dose. These products separate in the bottle (pour some in a clear graduated cylinder and see overnight the separation of clears). After some time this has caused the imbalance> Thanks again, Adam Have you read through our archives including here: http://www.wetwebmedia.com/calcalkmar.htm Best regards, Anthony>

Re: High Calcium / Low Alk Thanks Anthony, I have more information now.  OK, yesterday (before I got your email) half of my fish were breathing very heavily and very quickly, and were lethargic.  My blue damsel (who is the first fish added to my tank after cycling over 6 years ago) looked like he was dying for sure.  He was lying on the sand, and occasionally falling on his side.  As it turns out I also noticed that my skimmer wasn't functioning.  So, I aggressively skimmed for the past 24 hours, pulling out about 2 gallons of nasty dark yellow stuff, and performed a 20 % water change.  I also added fresh PHOSGUARD and carbon.   <excellent thinking and recovery strategy. Kudos> The blue damsel has come back to life!!!  Acting like himself again!!  So have the rest of the fish. Side question: when I began skimming, it was out of whack for the first two hours (over-foaming).  Is this related to any of what we are discussing? Have any theories? <too many possibilities for why... skimmate production is influenced by the integrity of the proteinaceous sheen at the surface, barometric pressure (bubble size), colloidal matter in the skimmer neck (helps climbing bubbles) and the list goes on> I now realize that my alk was never low at 4.5 meq/L, but I do understand the risks associate with having calcium and alk so high.   <whoa! My fault... I thought you meant 4.5 dKH (which would be scary low)... as meg/l go... it is fine and on the high end> My understanding is that my alk level is fine, but my calcium level needs to be more like 400-450.  Would this be safe, and considered 'in balance'? <agreed> >One last question that has been driving me crazy:  I just ordered an RO/DI - it will be here within a week.  What additive do you use to prepare/reconstitute (match your pH etc) for RO/DI water?   <tons of info on this topic in the archives of wetwebmedia.com  The gist of it is to aerate your water first... then buffer it slightly... mix well... then salt (a 36 hr or longer process). No need to remineralize the purified water to high alk... just med tap water levels is fine> What effect, if any would this have on the balance we are discussing above. <it will be negative if carbonate buffer/solutions are abuse (excess)> Thanks Anthony,  you saved me from a potential crash.  My fish thank you also. Adam <our great pleasure. Anthony>

Calcium Reactor affects on tank alk/Ca level Dear WetWeb Crew: <Greetings, Kevin, JasonC here...>> Once again I need your experience in answering a question I have; your previous responses to my past questions have always resulted in success for me with my 2 yr. old 100 gallon reef tank. After several months of non-use, I have started to again use my Korallin Kalkreactor with a 75%/25% blend of Korallith and CaribSea reactor media; prior to restarting the reactor, I was using 2 tsp of Kalkwasser/1 gallon distilled water to maintain alkalinity and calcium, but with the reactor running, I have decreased the amount of Kalkwasser I added to the distilled water to 1 tsp.  I also do a 10 gallon water change every week. After 2 weeks of running the reactor I was hoping you can help me with some questions regarding the properties I have measured. Tank water: Alkalinity - 4.2 meq or 11.8 dKH Calcium ? 320 - 330 ppm Reactor effluent (drips into sump water over a submerged Aqua C skimmer Rio 2500 pump): Alkalinity ? 13.8 meq or 38.7 dKH Calcium ? 480 ? 490 ppm I mentioned that the reactor effluent drips into the sump into water that is over my skimmers pump; I do this to insure that any excess dissolved carbon dioxide is pulled into the skimmer and vented off by the agitation. Tank pH is 8.3. After always reading that tank level calcium needs to be maintained 400 ppm or higher, I was concerned that my calcium level in my tank was to low, but since using the reactor my Tridacna derasa and squamosa are showing increased shell growth, my just added Caulastrea coral is plump and extends feeding tentacles at night, coralline algae is covering all the rocks and has to removed from the sides and front tank glass regularly, small polyp corals that had disappeared prior to the use of the reactor have started to show themselves again and the fish continue to be active and feeding aggressively (even my powder blue tang). The only possibly negative change is my two Sarcophytons do not extend their polyps as fully as they did prior to the reactor, but the main body of each becomes fully erect once the lights come on in the morning and both Sarcophytons are getting larger, taller, and plump. My question (sorry for the long introduction!) is am I worrying to much about my tanks calcium level vs. what is said in popular literature and in reality, based on the reaction of the tank inhabitants, is everything in good stasis. <I would say yes. If you had the opportunity to go and measure dKH and calcium levels around the world, you would be hard pressed to find the high numbers which people tell us we need. There is balance somewhere in the middle as evidenced by the growth of your clams and coralline algae. I know that high alkalinity: I calcium are mutually exclusive, but why is the reactor effluent calcium level not affecting the tank calcium level as much as the reactor effluent alkalinity level is affecting the tank alkalinity level? <My thinking here is that the effluent dKH is too high. You need this to be in the range of 15-ish. Anything higher will make it difficult for the calcium to go into solution, and more likely will precipitate out, forming deposits on the effluent valve and elsewhere. Do recall that the enhanced alkalinity brought about by the reactor will cause the calcium in your sandbed and live rock to add to available calcium. I would try just a little less CO2, and continue with the same drip rate. Ideally, you want the effluent to be at about 15 dKH and the pH to be about 7.6> Is it that the calcium level in the tank is being used up at a greater rate then the alkalinity? <That is a factor, but I'd try lowering the dKH of the effluent first - much easier to affect changes here.> Any input you can supply on this would be much appreciated. Thank you in advance. Kevin <Cheers, J -- >

Alkalinity and pH I have a quick question about alkalinity. Last Wednesday I brought home an Elegant Coral and a Open Brain Coral. <both are placed on the sand bottom right? They must to survive... see archives here at WWM> By the weekend the Elegant Coral had developed brown jelly disease and infected the open brain above it. <above it suggests placement of at least on rock. Hmmm... free-living SPS corals become stressed and abraded when polyps cycles cause wounds and tears on live rock... leading to infection. May not have been your problem... could have been shipping/handling if they were new at LFS. Still... you sound like a new aquarist. Do consider that quarantine is necessary for all new fishes and corals (4 weeks in a separate tank). This prevent s the spread of such infection s to your whole tanks, saves lives and has many other benefits. Please visit the wetwebmedia archives on this topic as well. Also... buy a good reference book and read it to guide your purchases before bringing livestock home my friend> I immediately sucked the disease off them and removed them from the tank. I fresh water dipped them and tried them again. Of course too late, the next day I removed them completely. <indeed... it is highly contagious/virulent. Best treated in QT for any chance of survival and more so to protect the rest of the tank> Since then (Sunday) I have been fighting a low PH. <not caused by the corals of course... if anything, the waning pH of the system stressed the corals and was a catalyst> About 7.8. <Doh!> I have been adding Kent PH Buffer. Today it is about 7.9. The thing that scares me the most is my alkalinity is 16.32. <holy cow!> I checked twice yesterday which was over 18 and today it is 16.32 (DKH). What can I do to lower this and raise the PH at the same time?   <dilution is the solution to pollution: water changes. And if your Ca is low (under 375ppm here), use Kalkwasser to raise pH without raising Alk directly> I haven't been adding any 2 part calcium additives at all. Just the Tropic Marin Calcium. <sounds like things have gotten out of kilter. Several large water changes and then resume with Kalk/buffer or 2-part mix (but shake very well before every dose... critical!)> Thanks, Ian Roff <best regards, Anthony>

Ca/Alk This is like the never ending question, sorry, but I am learning so much from this conversation. <indeed the purpose my friend> The reason for using the Seachem Reef Calcium and SeaBuffer is to maintain proper Ca & ALK levels.   <agreed on premise and half on application. The SeaBuffer is fine and necessary for buffers (carbonates). The Reef Calcium however does not maintain readily USABLE/assimilated calcium for coral growth. Its a great product for corallines, but not recommended for almost any other calcifying reef animal no matter what your test kit reading says. This unfortunate reality is time tested. Calcium gluconate is a supplement to Kalkwasser and for growing corallines but should not be used as a primary vehicle for Ca maintenance> What I didn't think to tell you was I have been adding Sea-Lab #28 blocks since week one. <OK... but here you have a problem with accumulating Chloride ions. Please, my friend... if you do not delve deeper into the chemistry of it (no fun anyway for most), trust me: The two best ways to provide calcium for your tank are Kalkwasser (calcium hydroxide... or calcium oxide) or a calcium reactor. Liquid or dry calcium chloride has significant issues and pitfalls with proper use, and calcium gluconate is not useful too much beyond corallines> According to their booklet this includes Calcium, Strontium and all trace elements and in fact further state that Ca is 400.0 ppm. <not as a long term solution in my opinion. A good product for small tanks with large water change schedules. Else, Kalkwasser for bigger aquaria (over 40 gallons)>> Am I good with this product? If not, should I use Seachem along with Sea-LAB #28 already added? <neither... Kalk and SeaBuffer if not using a calcium reactor> As to ALK, I also have (not used in this tank yet) Sea-LAB #14pH which controls Alkalinity. Would this product work as well? <possibly... little to go wrong here. I do like most SeaChem's products very much. A fine company> I have no problem getting the product you suggested, I'm sure you have great experience using these and feel confident is suggesting them and I appreciate the advice. Just wondering if I should/could use what I have on hand? <target the ingredients used and not the brands. Calcium chloride and calcium gluconate are deal breakers in any form by me> As always "Thank You" from the bottom of my fish tank :-) Dave <cool... I have never been thanked from the level of detritus before... humbling <G>. Best regards, Anthony>

ppm or dKH?/Ph update Well, my Ph didn't rise a bit after aerating, still 7.8,..UGH! Even my Alk seems to have fallen a bit from 11dkh to 9. I don't get it? <no worries... this actually makes things easier for us. Your Ca is high and does not need any heavier Kalkwasser. You will continue to test and dose Kalk to stay in the 400ppm range. Now with your ALK and pH depressed... they indicate the need for simple buffers. Baking soda will be fine here. Use small amounts and be patient (too fast dosing can precipitate out and get really ugly). This sodium bicarbonate will raise your pH and Alkalinity. If you find it easier... buy and use a two part supplement (but do a water change or to balance Ca and Alk before starting dose... you must begin in balance to continue in balance). Or perhaps a Calcium reactor is in the plans down the road for you. Both are easier than the Kalk and buffer seesaw... but they are a lot more expensive too. Kalk also has many benefits over all. The lack of a pH rise after aeration is a good sign> Maybe I should attach airline to another of the powerheads... it doesn't do much for the aesthetics of the tank however. <to be specific, dear... my recommendation was to aerate a glass of water. Aerating the whole tank is too easily influenced by other factors (DOC levels, bio-load, feeding etc). I suspect that aerating the sample glass will not be much different though (no change). Still.. to be sure, run that test. The venturis are a mess on the tank. Too many bubbles, irritates coral and some fishes, causes salt creep. Again, my recommendation for aeration of we needed it was a better skimmer (more oxygenation here) or an extra airstone in the sump> I hope to find a better way the increase circulation once we figure out this problem. Maybe I feed too much?? <feeding does burden this process... but I'm inclined to feed heavy myself and compensate with good water changes and aggressive skimming, carbon, etc> About every other day, my 3 clowns, 5 assorted shrimps, 3 dominos, and 3 (?) fish all enjoy fresh from the beach chopped assorted snails, you know, the type that wash ashore stuck to the rocks. <very dangerous to feed in the long run. Disease and metal contamination in the flesh. Unless you live on a rural Australian coastline, you simply reside too near (big picture... 100 miles above and below your coast) industry and people. The first several miles of water on this and most any beach are off limits in my book for water or food collection. The diseases you could bring your fish alone are scary. At least freeze the snails first for several weeks or more to kill off some possibilities. Still not fool proof> Then on and off I give them a bit of flake Marine food and Spirulina algae. Would you be happy on this diet?? <it is a very limited diet. Lacks fresh vitamins and fatty acids. Keep your flake and Spirulina, freeze the snails, add frozen Mysis shrimp, gammarus shrimp and or plankton/krill (frozen), and perhaps a quality pelleted food (perhaps in stead of the flakes). Vibra Gro ranks high for me. Nori seaweed for tangs and angels too (dried)> Oh yes, 75 gallon tank. Thanks my friends!! Pam <best regards, Anthony>

High Calcium & Alk Hello! <Hi!> I would like to thank you in advance for your time and apologize for the length of my email. <No worries...We enjoy answering questions> I have an established (18 months) 125 gal saltwater tank. I am using a sand substrate 2-4 inches (varies from spot to spot because some of the fish move it around) with 135 lbs of live rock.  My water parameters are calcium 405, magnesium 1150, alk/dKH 12, <A calcium and alkalinity that high is a difficult feat to accomplish. I would be careful of letting them get out of hand and rising too high> ammonia 0, nitrite 0, nitrate (impossible to get a clear reading was using coral vital <You would be wise to leave that "snake oil" out> but I have stopped adding it for last 2 weeks and don't plan on continuing) after >calculation 7, Strontium off the chart >40, pH 8.2 in the am, iodine .08, sg 1.024, temp 78-80. <All sounds good>  

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