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FAQs on Avoiding, Treating Parasitic Disease with Hyposalinity: Dangers, Provisos

Related Articles: Hyposalinity or Osmotic Shock Therapy (OST) by Pete Giwojna, Marine Parasitic DiseaseMarine Ich: Fighting The War On Two FrontsQuarantine, Quarantine of Marine FishesSpecific Gravity, Salinity,

Related FAQs: Using Hyposalinity to Prevent/Treat Marine Parasitic Disease 1, Hyposalinity Treatments 2, Hyposalinity Treatments 3, Hyposalinity & Ich, & Hypo Methods, Protocols... Hypo Success Stories... Hypo Failures, or Not Quite Yet Success Stories... & Treating Parasitic Disease, Marine Parasitic Disease, Parasitic Disease 2, Parasitic Disease 3Parasitic Disease 4, Parasitic Disease 5, Parasitic Disease 6, Parasitic Disease 7, Parasitic Disease 8, Parasitic Disease 9, Parasitic Disease 10, Parasitic Disease 11, & FAQs on: Parasite-infested Systems: Parasitic Marine Tanks, Parasitic Marine Tanks 2, Parasitic Reef TanksParasitic Reef Tanks 2, & FAQs on: Preventing Parasite Problems, Diagnosing Parasitic Diseases, References on Parasitic Diseases, Index Materia Medici for Parasitic Diseases (medicines), Treating Marine Parasitic Diseases, Using Hyposalinity to Treat Marine Parasitic Diseases, Hyposalinity Treatments 2, Fallow Tanks, & Best Crypt FAQs, Cryptocaryoniasis, Marine Ich, Marine Velvet Disease Biological Cleaners,

Most invertebrates, algae, vascular plants can't take rapid or extreme changes in specific gravity w/o suffering ill effects. Fishes too have a variable... by species, specimen, size, health status, reaction, resistance to troubles exposed to changes in Spg.

Do beware of a loss of nitrification & alkalinity

Quarantine & Hypo   6/12/12
Hey everyone hope all is well and as always thanks for your help.
I have been QTing my new fish including tangs, Anthias and gobies and other than a slippery fire goby that managed to jump out of the only small gap on top of the tank I have had them all going for 5 weeks (7 days dropping SG to 1.009 and 28 days at 1.009). The fish have shown no sign of white spot at all and have been eating well the whole time. My first question is what SG is required to effectively eradicate marine Ich.
<... am not a fan of this treatment mode. Read here: http://www.wetwebmedia.com/martrthyposalfaqs.htm
and the linked files above>
I have heard levels as low as 1.006 through to 1.009 (most common) and up to 1.012. Will all these levels kill the free swimming parasite?.
<Not always; perhaps never>

 Secondly what is the best length of time to QT in hypo. Am I OK to start lifting the SG over the next week and then transferring the fish to my main tank or should I run a lower salinity longer.
Thanks for your help and guidance.
<Keep reading. BobF>

Loss of Color     2/19/12
Hey Guys/Gals. I have a quick question. I am currently treating my fish with Hyposalinity. Haven't seen a spot in 4 weeks. My concern is my Blue throat Trigger "male" Has lost some of his color since being in hypo. Other than color loss, he looks and acts perfectly normal. Is this normal, could it be stress? Should I be concerned? Thanks.
<Is normal, is due to stress, and concern... Should be fine once the fish is returned to regular conditions. Bob Fenner>

Pete Giwojna    1/21/12
Hi Bob, I wanted to ask Pete  Giwojna a few questions about a few of his articles. Do you have a number, maybe his email address? Thanks, Jim
<Mmm, I don't give out others contact info., but have Bcc'd Pete here, and if this doesn't work, I'd suggest trying to write him through OceanRider.com
Re: Pete Giwojna  1/21/12
Hi Bob, I was just curious if he ever did a follow up on that 250 Angel tank?
<Ah, don't know>
I seen a few people were writing a couple of years ago, but you never heard anything new about it.  I do think hyposalinity does nothing.
<Well, is at least unreliable>

It seems to only work with certain fish that I think are less prone to it.
I have a Powder Blue, and Brown Tang. It never got any worse, but every night they were covered with spots. Finally had to do the copper.   Jim
<Let's see if Pete writes us back. Cheers, BobF>

Hyposalinity/Disease Treatment  - 03/27/06 Hi Bob,  <James today> I tried to find the answer on your fabulous site, but couldn't find what I a looking for.  I have a 120 gallon  live rock and sand tank with a protein skimmer and a hang on filter.  I have been running this system this way for 2 years.   I recently added more fish and I think I maxed my fish capacity for the filtration level on my tank.  As a result I started to have some water quality challenges.  I have been fastidious about quarantining new fish and watch my water quality carefully.  I did a big water change that I get from the local aquarium to compensate for my water quality drop.  I am now convinced I got Ick from the aquarium although I am sure that the aquarium filters its water.  I have never had Ick in this tank. My question.....I have brittle stars, hermit crabs and some anemones and I am thinking about lowering the salinity on my tank to break the cycle of the Ick.  Would the brittle stars survive a lower salinity?  I know the hermit crabs can.  The brittle stars would be difficult to collect since they live under the rock.  Do you think this is a good choice for dealing with my Ick problem.  <Do read here Dawn.  Do look at related links on this page, also. http://www.wetwebmedia.com/martrthyposalfaqs.htm  Others have had the same problem, see what was suggested in the FAQ's.  You can read what you are dealing with here.  http://www.wetwebmedia.com/ichart2mar.htm>   Removing all my fish from the aquarium and letting it go follow for a month would be a nightmare for me as I have a lot of fish and the daily water changes in quarantine is exhausting.  If I remove and treat sick fish than they will get sick again when I put them back in my tank.   I know I need to address the Ick issue some how and soon.  I would love to get some cleaner shrimp and a cleaner wrasse, but my eel seems to have an appetite for both. He has had some expensive dinners in the past.  <So has my wife.> I am going to add some additional filtration to address the water quality challenges. I am also adding garlic to the food. What do you recommend would be the best approach given the information.  Do you think lowering my salinity would be a good course of action and would it be safe to leave brittle stars and hermit crabs in tank during this process? <Consider UV Sterilization.  It will help. Aloha from Hawaii,  
<Bob is there as we speak, totally bummed out.  Nothing to do but dive, have cookouts, etc....boring. James (Salty Dog)> Dawn Re: Hyposalinity/Disease Treatment  - 03/27/06 Thanks James,  <You're welcome.> Oh I feel so sorry for Bob vacationing in Hawaii.  It has rained here for a month straight and today we have flash flood warnings.  Let him know that he unfortunately came for some of the worst weather I have seen in ten years. <I'm sure Bob is aware of that and will read and possibly comment.  And don't feel sorry for Bob.  He has a life I dream about.  Very busy, but rewarding.> <<Actually, not busy at all, but a great deal of fun. RMF>> I have a 15w UV on my tank already.  Is that too small for a 120 gallon.  <To be very effective I wouldn't run more than 400gph through it.> Is it worth upgrading to a larger size in light of my situation? <Don't think so.> I read the articles on low salinity and Ick.  Do you think it would be wise to remove fish now (dreaded all fish and a nightmare of water changes to boot), my fish are showing no signs of distress yet.  Is waiting it out until I see distress a mistake?  In past systems my fish have over come the Ick with improved water quality and garlic.  I fear I may have a heavy infestation. You know who quickly it all can turn......What would you do?  <What I would do is move the fish into quarantine and treat.  Let the tank go fallow for one month to insure all cysts have passed on to a better world, then re-introduce the fish back into the tank.> Thanks again,  <You're welcome.  James (Salty Dog)> Dawn

Treating ich/itch... Having read all I can about itch treatment on your site, I have decided to try hyposalinity first and fallow my tank for a 8 weeks. I would however like to know why bob, you don't seem to favour hyposalinity <Doesn't often "work", too hard on many species, impugned specimens... that is, more stress than it's worth...> and if so, what then is your preferred method for treating itch in general? <... this is posted... on WWM. BobF>

Copper treatment side effect? Dear Bob: <Eric> My fishes are in the QT with copper for a week, and because the salinity was lowered to 1010, therefore I was trying to raise it slowly day by day by changing 4 gallons of water daily (20 gallon QT). my Regal angel today show signs of distress. She seems to be not able to keep his posture, as like she is trying hard to not float up to the top. her head tilt down and swim backwards/side?? She is breathing rather fast but she seems alert, (eyes are looking and moving). she is not breathing really fast. but faster then normal. however all her tankmates are fine. Will the fish's floating device malfunction if I am raising the salinity too fast? And how fast is too fast?? <A ppt (part per thousand) a day is about safe for fishes... two ppt maximum "going up" (one going to lower Spg). The combination of altered salinity AND copper is too much for some species, individuals. Bob Fenner>

- Hyposalinity/low pH Problem - I am QT'ing a small 1" yellow watchman and a 2.5" coral beauty in a 10 gallon tank. It's been 2 days since purchase and, predictably, the CB now has ich.  My preferred method of treatment is hyposalinity. It seems to work every time; the only drawback however is that once my salinity is leveled off at 1.009-1.010, the pH drops dramatically (especially at night), even though I aerate and buffer the change water (which reads 8.2-8.4 ph when I add it in) a day in advance. Now matter how much buffer I add, pH dips to 7.6 at night. I use DI water for the change water.  I'm going to lower my sg over the next 2 days to fight off the ich for 14-21 days, and I'm dreading the low ph already..... Any suggestions?  <I'd try adding buffer to the quarantine tank directly. Baking soda will work fine as it's difficult to overdose. Still, take a small vessel of tank water, mix in a teaspoon of baking soda and add that mixture to the tank. Wait an hour or so and then test. Would consider adding it in the evening before the lights go out. Cheers, J -- > 

Clown triggers swollen, hyposalinity... issues of too much money, too little knowledge Hi crew, I need your precious help to solve a great problem. I'm making hyposalinity in my tank (250 gallons) for fighting Cryptocaryon. A week ago I've brought my salinity to 13 ppt and now my fishes are free of white spots. But two of them (medium clown triggers) have their belly very very swollen. <... likely as a consequence directly of the lowered Spg... and a comment re the two Clowns in one tank... not a good idea... you will likely have a great deal of antagonism, stress overall here> I've bought one of these two clowns Saturday and after a eight hours acclimatizing I've put him in my tank. <...! You put new fish in an ich/crypt infested system? Without quarantine?... Why?> Yesterday he had his belly swollen like the other clown who is in the tank from the beginning of hyposalinity. Another clown trigger is died 3 days ago this is body swollen. <Stop!> All other fishes are ok. Now I have put the two swollen triggers in another tank with 35 ppt of salinity to save their lives. <Are you moving these fishes between these differing densities of water immediately? As in within a day? Not good> Is possible the reason of this is too much salinity because of wrong calibration of my refractometer. What can I do to save them? Please help! Thank you very much Lorenzo <Lorenzo... please study www.WetWebMedia.com re Cryptocaryon, Hyposalinity, Clown Triggers, Quarantine... go to the homepage, use the Google Search Tool there. Much to learn my friend, that will save you worry, money, lost livestock. Do NOT buy any more livestock, or manipulate your water quality until you understand what you're doing. Bob Fenner>

Hyposalinity Or Medication For Ich Treatment? Hi crew, <Hi there! Scott F. here today!> I have, am having serious issues in battling ich this time around. <Uh- Oh...> All of my fish (1 Flame Angel, 1 Valentini Puffer, 3 Firefish and 1 Neon Goby) were infected with ich. I removed all from my 100 g. and put them into 2 separate 10 g. QT cycled tanks. The Flame Angel Beat up the Firefish so I got a second-hand 29 g. with a divider and moved all fish in there. I lowered the sg to 1.010 and ever since, I'm having bad water quality issues. I tried Bio-Spira but it doesn't work at that sg. <Not sure of that- I would follow the manufacturer's guidelines to the letter. I've never been a big fan of hyposalinity for a variety of reasons, but regardless- water quality can be brought in line through good husbandry techniques...> I change 10 g. twice daily in effort to reduce nitrites. Ammonia is now 0, nitrite usually 0.1-0.2. I was using tap water for the change water but the chloramines (.25 ammonia even with Prime) were creating larger nitrite spikes (.5). I am running to my LFS daily to get 20 gallons of DI water. <Unfortunate, but your solution is a good one, given the circumstances...> It's been almost 2 weeks and it's getting very expensive and time-consuming. I spend 5 hours a day changing/getting water. I can't install a RO unit at this time. <I'm sorry to hear that...It sounds like actually procuring the water is eating up most of your time? Daily water changes are not a great idea in a situation like this, IMO. Possibly more disruptive than helpful. Consider increasing the SG (gradually, of course) back to "normal" parameters. This will allow you to use the currently ineffective "bacteria in a bottle" product. You could then treat with a common over-the-counter ich medication, such as copper sulfate (for fishes that can tolerate it) or a formalin-based product.> To make matters worse, it's been 10 days of hyposalinity and the fish have ich again. I lowered the sg to 1.009. My flame angel's lips are white (probably from bad water quality). <Hmm...not sure about the cause, but water quality is certainly a possibility> All fish are still eating. I think the cure is worse than the disease at this point. <Well, as I've previously stated- I am not a big fan of hyposalinity. Not to say that some medications are any less stressful, but they do have proven track records.> I think I might have to raise the sg back to normal, and use some other treatment. <We're on the same wavelength!> I've had success with hypo in the past, but that was only 1 fish at a time not 6!. I'm probably not siphoning all the eggs out (the Firefish are very jumpy and prone to fly out of the tank when I siphon). <Understood> Should I continue hypo, and if so how long? Should I treat with formalin too? I can't use copper because of my scaleless fish. My main display is fallow (I'm keeping it this way for 4-6 weeks). <Regular specific gravity and formalin-based medication would be my recommendation> Thanks for any advice you can provide Tired, Angela <Do a little "course correction" here, Angela- and carry on from there! Good luck! Regards, Scott F.>

Ich Problems... I have been having problems with ich in my main tank. I spoke to my supplier who had recommended that I lower the salinity to 1.015 which I did. That was about six months ago. I have  had several fish (Kole tang, and Emperor Angel) die on me during this time. <That is a bit low for a long term sustainable system> My water seems to be fine - pH is 8.2, alkalinity 10 and ammonia low. The only item which is low is the calcium. As I have no coral in the tank, that was not a concern. I bought another Kole tang from my supplier and it died within 3-4 days. <Lots of possibilities here, some of which may have been beyond your control (i.e.; the fish may have been sick prior to your purchase, etc.)- part of the reason that I'm a huge fan of quarantine> The Kole was covered in ich . I decided to get another opinion from another supplier in town and they said that my salinity should be brought up to 1.021 as I am putting the fish under stress for the long term. <I agree with the supplier. Hyposalinity may have some merit in certain situations, but I feel that a more "natural" specific gravity is better for long-term success and overall health for your fishes> I am getting conflicting advice . Can you help me? The other fish in the tank seem to be OK - a Sailfin Tang had some ich but it disappeared after a week. I also have a Cuban Hog, Flame Hawk, Moray Eel, Yellow Tang and Naso Tang. I have been adding Coral Vital to try and treat the ich prophylactically but it doesn't seem to have had much effect. <It wont...'nuff said on that!> Thank you. Vito <I believe that your problem may lie in two areas- selection and acclimation/quarantine. It's important to be very careful when selecting your fish. If they are showing any signs of illness, or in a tank with fishes that may be showing signs of illness, you really should pass. Be sure to embrace a quarantine procedure with every new arrival. The process has been written about extensively on the WWM site by yours truly and other authors. In quarantine, you can observe the fish carefully and treat easily if disease manifests. I think if you are more careful in these areas, then you will see a dramatic improvement in your success with your fish. Good luck! Regards, Scott F.>

Hyposalinity In The Quarantine Tank Thanks for the input on recommending 1.025 salinity for the main tank as opposed to 1.008 to 1.012 for the long term health of the fish..   <You're quite welcome! I think that your fish will definitely benefit> My question now is whether or not keeping the Specific gravity at 1.008 or so in the QT tank for about 3-6 weeks before slowly raising the salinity back to 1.025, would be safe for marine fish? <That would be fine. I prefer "normal" specific gravity all the way, as it simply is one less acclimation when it's time to add the new guys to your display tank, but there are many people who use hyposalinity in quarantine with no problems at all.> How long would you recommend fish should remain in 1.008 without ill effects? <Weeks, in my opinion> I just read some info about keeping the salinity this low in your QT will dramatically reduce the length of time your new fish should be QT'd, say from about 4 weeks to about 2 weeks or even less due to the fact that some marine parasitic infections are easily killed off without the use of copper or any other chemical based fish medications in near brackish water conditions. Is this true? <Umm, partially. Hyposaline conditions can help prevent some parasitic conditions, as many parasites cannot tolerate lower specific gravities. However, I would not use hyposalinity as a "shortcut" to lessen the quarantine period. The full 3-4 week period is enough for most symptoms of dreaded parasitic illnesses (like marine ich or Amyloodinium) to manifest themselves.> Also, is hyposalinity effective for eradicating awful and virulent diseases such as Amyloodinium or Brooklynella, since I plan on adding clownfish to my main tank? <Well, there is still much debate on this. I've even read some reports that say that freshwater dips are relatively ineffective against these illnesses. However, I'd rather try them myself before chemicals. The best way to prevent these scourges is to select your fish carefully, and to use the full quarantine period. Make sure that you obtain captive-bred clownfish, as wild-caught ones are more prone to these virulent illnesses. Best of luck to you! Regards, Scott F.>

Omnipresent crypt? hi guys, well maybe you can explain something to me. I'm confused. I'm under impression that Ick is always present in a marine tank. so what happens is a fish gets stressed, for whatever reason, and losses his slime which allows for the Ick to attach.  is this right, the whole story? <Mmm, no. There are Cryptocaryon-free systems... and there are systems that do have latent, low-pathogenic loads of this and other protozoan parasites. Often there are environmental influences that trigger, pre-dispose more full-scale infestations and possible related mortalities... as well as nutritional inputs, genetic...> so I'm thinking why don't I just keep my salinity at 1.016. I mean besides keeping everything else in order. <Mmm, well, low Spg is in turn stressful... though many stores, wholesalers purposely keep their water less than natural seawater strength, this is not encouraged for the vast majority of permanent displays> is there a way to help fish keep their slime, besides not stressing them out. <None that I'm aware of> I do not understand separating fish from the main tank when Ick is constantly present.  it seems just as stressful on the fish. I know Ick is a never ending battle. oh well, forward march. <The logic of removing fishes from an infested system embodies being able to treat them while not destroying the biological filter and other micro- and macro- non-fish life in the main display, yet encouraging the death of fish-host parasites in their absence... and allowing the parasitized fishes to be treated separately in an environment that is hostile to non-fish life. Bob Fenner>

Hyposalinity Treatment? Hi Scott, just come across the following OST method recommended by Saltaquarium website: http://saltaquarium.about.com/cs/diseasesich/a/aa102797f_2.htm I think this method is much easier and quite suitable to my current FOWLR tank, but just want to get your opinion before I try (it require no removal of fishes from main tank). <Well, it's the old "hyposalinity" trick...Sometimes it's effective-sometimes it isn't! I have never personally liked it, myself, but many hobbyists report good results with the technique> Also, will the Caulerpas in my refugium survive with such low s.g ? Thanks. Best regards, PJ <Well, PJ- it's hard to say. Quite possible that the Caulerpa population could "crash" with the decreased specific gravity. Good luck! Regards, Scott F.>

When should I stop? Quick Question. At what point will lowering the specific gravity adversely affect my biological filter media?  At what point will it stop to grow good bacteria on the media.  Specific #'s would be great. <NSW, near sea water conditions are best. That is, a specific gravity of 1.025 is ideal... and keeping this about here (topping off regularly, adjusting new water carefully) is very beneficial. For treatment with hyposalinity, any drop/change in Spg will adversely affect nitrification. ANY. You should monitor aspects (ammonia, nitrite) daily, be ready with new water for dilution, perhaps chemical filtrants, pre-made biological filter material... if lowering Spg, or raising it.>          If you want some details leading up to this question read on, if not thanks for your help!         I have a 120 gallon main tank a 20 gallon quarantine and a ten gallon hospital.  All tanks are biologically alive with all parameters in check.     The reason I have all the tanks going is that I just got a majestic angel about a week ago, I know what you are thinking but I did my research and realize what I'm up against and took 7 months of going to my LFS to find the perfect specimen.  The problem occurred when I introduced some Caulerpa to the main tank for a treat for my powder blue after a quick rinse without quarantine," bad move". I've been doing this for 5 years now, will I ever learn.  Within about 5 days the tang had some spots, I caught him gave him a dip then returned him home. Three days later you know what.  Unfortunately I'm in it for the long haul now at least 45 days.              So now I have three tanks set up and running. A ten gal hospital barebones with a powder blue in it which I'm am treating with hypo salinity and formalin dips plus my own tank/filter creation which has a high enough turn over rate to successfully filter out that pesky littlie protozoa but allows me to segregate the bio filter. A 20 gallon quarantine tank with 8lbs of live rock, live sand, tang haven algae two power heads and a whisper 30-60 which I modified and put  bio wheels in to boost it's efficiency, one Chromis and a majestic angel.  Did I mention I have now found a few spots on the angel?   <Now you have> So lets break it down I have three tanks with Ick and five fish I have to find a place for to let the main tank go fallow for about two months.  Yes. I do have cleaner shrimp but about all they're good for is making babies and stealing food from the Anemone, Its a good thing my two Perculas are great protectors.  I have a written protocol for all new fish but slipped on the algae.  I always use my quarantine first then if the new fish have parasites I put them in my hospital which I will establish 1 week or more ahead of getting a new fish by a sponge filter from my main tank  then I can let the quarantine go fallow for a month while I treat the new fish in the hospital tank without drugging up the water then after one month they go back in the quarantine tank for another two weeks. I always try to keep from using meds, except in dips, if I can at all avoid it.  If there still alive after all this then they make it into aquarium paradise, if not then at least I didn't contaminate my main display. I have about a 85% success rate.  I thought I had a fool proof system. I guess the fool didn't fallow the system.                    Without the books of Bob F. and articles on this site I wouldn't have ever stayed in this hobby.  You guy's are the Bomb! <Be chatting, Bob Fenner>

Hypo-salinity and Hydrometer Accuracy Hello Bob, Steven, Jason, and the rest of the crew, This is my first question for you so I want to say that your site is wonderful and has provided me with a wealth of information, which has allowed me to be much more successful at this hobby than I could have ever thought.  Without this site, I would likely be one of those in and out reefers who drops the hobby after a year, now I'm hooked for life.  I'll keep this short, no story behind why I'm asking.  I am having a problem with hypo-salinity treatment.  I believe that my hydrometer readings are off.  I have three: a Deep Six, a Sea Test box-style, and a floating glass (with a built in thermometer and made for aquarium, rather than lab use).  All three read differently!  So I chose to trust the floater because I have read the others can drift over time and both are not brand new.  I have conversion charts galore, but they are worthless if you don't know the calibration temp of the hydrometer or if the hydrometer is not accurate anymore.  I believe I am failing to maintain a proper 1.009-1.010 SG and that my true SG is more like 1.012-1.013 (this would be true if the floater were calibrated at 60F).  After three weeks in hypo and several FWD's my fish are still showing spots and scratching a bit. >>Do know that there are documented subspecies of Cryptocaryon irritans that do quite well in low salinity environments. >Questions:  Is there any way that I can mix a test sample of water with a controlled amount of salt (I have Instant Ocean brand) at a specific temperature in order to test the accuracy of each hydrometer?   >>Yes.  I would first calibrate with distilled water. >Is there any other way for me to be sure that I am at the proper SG level?   >>Yes!  Invest in a good quality refractometer! >Even if I am now at 1.013, is it possible for the ich to be so virulent as to survive that, and continue to re-infect my fish?   >>Yes.  This would necessitate the utilization of copper or formalin treatments. >Can the spots I see be bacterial infection from the parasites bursting out during FWD's? >>Yes, but not so likely as to keep the same appearance of the ich (at least not in my own experience, secondary bacterial infections really LOOK like infections). >With sincere gratitude, Manny >>Do a search on Terry Bartelme, he's written quite a bit on ich, treatments, prevention, etc.  Then, I would search the reefs.org library, as well as Advanced Aquarist for the same.  I've only recently learned of the ich subspecies, both instances mentioned by folks working in Hawai'i.  Hope this helps!  Marina

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