FAQs on Pond Algae, Control

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FAQs on Pond Algae, Control

Cyanobacteria in pond 7/22/09
Hello, Crew!
<G'morrow Anita>
I read your site everyday, soaking in the plethora of educated answers. I hope you now have one for me!

I have a one year old, 500 gallon pond, stocked with goldfish (mostly comets). It has a waterfall box and bio filter combination opposite a skimmer box. My problem is Cyanobacteria in the pond, and I have read the WWM article on this with great interest. This article explains why I have it; however, I'm not sure why I can't get rid of it.
<There are a few steps... all best approached together... nutrient limitation, competition, predation, shading... perhaps the use of UV, ozone...>
About 60% of the pond's surface is covered with plants (water lettuce, water hyacinths, parrots feather, and lily pads). I have submerged Anacharis and hornwort, which is growing wonderfully.
<Good, and good signs that your system itself is viable>
I also have some marginal plants (bog lily, umbrella palm, blue rush, Louisiana iris and sweet flag). The water lettuce is pale and yellow, and the water hyacinths are browning.
<Oh!>
The marginal plants are just not growing, and they have been in the pond since May (spring here in zone 5). The hardy lily is growing great, and I have had several flowers this year.
The average pond water temperature is 75 degrees F, and it gets sun for about 8 hours during the day. I add bacteria once a week.
<Mmm, this shouldn't be necessary... Once the system is established... I would not add such product/s>
My water is crystal clear in the very early morning and in the late evening. During the day, it is cloudy. This water clarity cycle has been going on for several weeks.
<A natural phenomenon seasonally>
Here are the water test readings:
Nitrate/Nitrite = 0
Ammonia = 0
Ph in the early morning/late evening = 8.2 (water is clear)
Ph in the afternoon = 8.8 (water is cloudy)
<Also a natural "swing", though high period...>
Phosphate = 4.0
<Yikes! Way too high>
I realize the BGA is feeding off of the phosphate and enjoying the high ph.
I have been performing daily water changes of about 5% for two weeks now to lower the phosphate and ph readings. My tap water's ph is 7.4, phosphate is 0. The water changes are not working. I also think that the marginal plants are suffering from the high ph reading by not being able to absorb nutrients, resulting in lack of growth.
I feed my fish once a day, and not every day.
I thought I was doing everything right, but obviously, I'm doing something wrong. Any advice and/or suggestions you can give will be greatly appreciated.
Thanks very much!
Anita
<I'd check your source water, other inputs (plant fertilizer?, Runoff into the pond?) for the HPO4 and dilute (through water changes mostly)... and look into the possibility of adding an ultraviolet sterilizer at the most extreme end... Please (re?) read here:
http://wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm
the fourth tray up from the bottom. Bob Fenner>

Fertilizing mistake in pond = overabundance of string algae due to phosphates 5/15/09
Hello, WWM Crew!
<Anita>
I really need some help with a "newbie" ponding mistake.
<Ok>
My 500 gallon pond is just under 1 year old and contains goldfish and plants. I live in zone 5, Northeast Ohio.
I planted a few new marginal plants about 3 weeks ago in aquatic planting media (NOT clay) and fabric planters. Well, the string algae starting growing and showing up like crazy, taking over the pond and choking out the submerged plants (hornwort, anacharis).
<Happens in such settings... newly unestablished ponds...>
I found out (the hard way!) that you cannot fertilize plants that are planted in aquatic media and fabric planters, as the fertilizer tabs leech into the pond, resulting in SUPER HIGH phosphate levels, which string algae just love!
<Ah yes>
Here is my dilemma: My phosphate levels are at least 10 ppm
<Yowzah!>
(the test kit tops out at this level). 2 days ago I added 1 dose of Phos-Out, and the level did not change. Yesterday afternoon, I performed a 30% water change and added another dose of Phos-Out. I tested the water again this
morning, and the phosphate level is still 10 ppm.
<... time to...>
What is the best, safest and quickest way to lower the phosphates?
<Take some water out, remove the fishes, dump all and re-pot the plants>
I did take the fertilized plants out of the pond, and I was planning on flushing them with water to (hopefully) get rid of the remaining fertilizer tab.
<Oh! Good>
On a positive note, I hope posting my mistake keeps someone else from making it.

Thanks very much in advance for your help!
Sincerely,
Anita
<As stated, the best course of action here is to simply dump, rinse, re-fill the basin... and change out the potting medium, use less soluble source of nutrient for your plants. Bob Fenner>

pond clarity question 5/13/09
Hello.
<Howdy>
WetWebMedia helped me last year with my pond. Many thanks for that.
<As many welcomes>
I have a new question: My pond is cloudy. I wouldn't say it had too much algae, and taking a glass of water from it, the water seems clear. But, it's hard to see more than 6 inches into the pond. Right after winter
broke, I could see clear to the bottom of the deepest areas of the pond -4ft or so. I've tried pond clarifier.
<Mmmm>
I have a UV light.
<How old are the lamps? Is it sleeved? When's the last time you had it apart and cleaned these?>
I have a good filter -tetra 4000 pressure filter- that matches the size of the pond and corresponding pump -also tetra. I don't feed overly much. And, I several plants. I clean the filter out every week to 2 weeks.
<All sounds good>
Recently, the power went out for 5 days... and the water cleared up. It was not so clear that I could see straight to the bottom as I could a month ago, but visibly clearer than when the pump was running.
<Ahhh!>
Why/how is that happening? What am I doing wrong?
<Likely nothing you're doing... but seasonal succession... bacteria, algae et al. profligating... I would be checking your water chemistry...
principally your pH, alkalinity (making these stable), and any measure of nutrient you can (NO3, HPO4) and making the last limited... through competition mainly... Perhaps shading>
What should I do with my pressure filter after it sat for 5 days with no oxygen?
<Backwash it thoroughly to waste... for several minutes... test some of the discharge water for free ammonia before setting it back on to your system>
Regards,
Martin
<Cheers, Bob Fenner>

Re: pond clarity question 5/13/09
I will do that. Thanks Bob.
<Certainly welcome. Do make it known if you have questions, concerns.
BobF>

straw types available for pond use... Alg. cont. reading 8/19/08
Hi,
<Hello there>
I was wondering if other types of straw can be used in keeping ponds clean, besides barley.
<They can... either by themselves or in combination...>
We are looking at a 20,000 gallon pond x 3. Barley would be very expensive and, and it would take a lot of it.
Thanks,
Warren Johnson
<Mmm, where would you like to start this conversation? There are many avenues for limiting, controlling pest algae... Depending in turn on many factors, principally water quality, the ready presence of simple nutrients, the overall purpose/desire of the keeper... Maybe start reading here: http://wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
and the linked files above. Bob Fenner>

Green water, pond... UV use 6/17/08
Hello again, I have another concern. The water on our pond is greenish in color, we tested the water and everything seem to be fine. It is a fairly new pond, and we have been running it for about 2 weeks now. Do you think we'll be able to see the bottom even if it is 4 feet deep? Our filter is an Ultima model (bead filter) which I am sure is sufficient for my set up. I am wondering if maybe it is the UV that needs to be replaced/addressed?
<Green water is often a good sign that the UV tube in a UV steriliser needs replacing. Do bear in mind the tubes in these devices lasts around 12 months depending on the model (check the instruction manual that came with yours for the precise details). UV tubes aren't expensive, and changing them is usually a 10 minute job, if that. Cheers, Neale.>

Pond Ozonator 4/24/08
I have a two ponds connected by a small creek and circulated by a biofilter and small waterfall. The total water volume is approx. 2,000 gallons. It does get direct sunlight, however, i have plenty of vegetation (mostly lilies) to shade the pond in the summer. The top pond is larger and contains several Koi and goldfish. The lower pond is smaller. This is where most of the waste and sediment ends up. I am having a problem with overgrowth of string algae in the creek, lower pond, and on the waterfall.
<Not atypical...>
I do not have the time or money to rip up the pond and start from scratch to try to get rid of the algae.
<You've read on WWM re ponds and algae?>
My pets like to drink out of the pond so I do not want to add any extra chemicals other than the dechlorinator and bacteria. I have read bits and pieces on the internet about ozonators and their success in eliminating nitrites which cuts back on the algae growth. I have been to several dealers even hot tub dealers) trying to get information on how to install or build one for my pond. No one seems to have any information in the area where I live Colorado). Any chance there is an article out there that you know of called "Ozonators for Dummies?" If you could give me any information on materials and installation I would greatly appreciate it.
Thanks,
John Kobza
<Please use the search tool on WetWebMedia.com
Bob Fenner>

Pond... algae treatment sans chemicals 4/25/07
Hello,
I have a question I have not seen addressed yet. We put in a small decorative pond at the beginning of the spring. Two water lilies are in the bottom and have a small waterfalls on the other end. My problem is the algae is just beginning to grow in the falls. The really big problem is I have several cats that seem to think this is their private watering hole. Is there any way I can treat the water organically or without chemicals so I don't harm my cats. I don't think there is any way I can keep them away from the water. I appreciate any help you can give me.
Thank you,
Kathie Phipps
<... To treat it for the algae w/o harming your cats, is this what you're after? Yes... through nutrient deprivation, physically (UV, Ozone...) and biologically... Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
and the linked files above. Bob Fenner>

New Pond, algae concerns - 08/15/06
Hello again,
 Just sent an email about my marine tank.
<Saw this... but don't see it transferred here... please resend to WWM>
Now for the pond. Actually this is for my parents' pond, and I would like to help them improve it. They are complaining of the algae and are almost regretting putting it in.
<Pond algae problems are almost as common as ponds themselves!>
They have worked way too hard to give up now, so I would like to give them some advice with your help. They have an upper pool that flows down a 2 to 3 foot
waterfall at 1500 to 2000 gph to the main pond. I would estimate it has between 600 to 1000 gallons total. Sorry can't be more accurate. I have
only seen it twice. The depth is about 3-4 feet in the main pond. They used a liner to construct the pond. My dad says it seems to lose about 2-3
inches of water every few days. Is this a leak or evaporation from the hot summer days?
<Mmm, this volume... could be either... should slow down with cooling weather if just evaporation...>
The algae is green and growing on the rocks. I know algae is to be expected, especially in a new pond. They live in northwest Iowa which does gets in the 90's often in the
summer. The pond is also in direct sunlight.
<Yikes... Have you/they read here: http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
and the linked files above?>
They have no livestock yet. They are smart and waiting. They do have some sort of a large canister filter that has bio balls and probably some other mechanical media in it.
Is this ok, or is this a nitrate factory?
<Helps, but will not solve algae issues... nitrates are not likely a large part of the issue here... the exposure to sunlight, high temperature, lack of photosynthetic life/competitors...>
 I am thinking they should add surface plants to cover about 60% of the surface.
<Yes>
They like lilies. Any other suggestions?
<Posted on WWM... floating "bunch" plants, Water Hyacinth, Lettuce... exposed plants will not likely overwinter in Iowa>
I have also read that barley straw will prevent algae growth.
<Can in some circumstances>
I will also tell them to minimize any nutrients including lawn fertilizer that may get into the pond.
<Yes, very important>
I don't think they have done any or enough water changes, only top off.
<Ahh, also need to remove some water in this process... lest a sort of "Dead Sea" effect ensue>
 What is the best way to remove the algae or kill it before removing it?
<Mmm...>
Does hydrogen peroxide work here?
<Not worth trying... the root causes will "re-constitute" the useful molecules back into algae soon enough...>
Does this dissolve the algae allowing you to do a mass water change to remove the nutrients?
<Not effectively, however...>
Would you use copper?
<Mmm, no... not unless I knew much more re this system, the make-up of the water... what life they intended to keep... and the system was much larger... Copper is too limiting in its use here>
I assume that they could drain and pressure wash the pond to clean it since they have a pressure washer. Or since this is the first year should they just leave it?

 I have a couple better ideas that they might be able to use. I was going to show my dad your design of the up-flow filter with the crushed rock. Or would they be better off using the upper pool as a some sort of bio filter?
<Either would be good additions here... the latter more expensive, but "faster" to get, institute...>
Will the up-flow filter prevent algae?
 <Only to some extent... Now... my ideas. We're this my pond, or my parents, in addition to the mentioned countervailing approaches... water changes, solids removal on a regular basis, using some live plants, adding more biological (including purposeful anaerobic) filtration, I would definitely consider adding either a good-sized Ultraviolet Sterilizer or Ozonizer in line with the water flow... after the new filter would be best. There are a few makers of these... But do want to mention, sing the praises of Vecton units (made in the UK by TMC, distributed in the US by Quality Marine, near LAX...)... as being very sturdy, practical for outdoor/pond use... This would/will be the shortest, most-assured improvement to ridding your parents pond of free-floating algal problems... and do a great deal more to assure good water quality... with the least amount of labor...>
Thanks again,
Joe Bosch
<Thank you for writing, sharing your concern. Bob Fenner>

Sick fish? Green pond... no useful data, cogitation 7/14/06
I have a 300 gallon pond. My 1st problem this year has been keeping the water clear. It insists on turning green (I only have about 4 hours of sun a day.) I have tried all suggestions to fix (from chemicals to plants) but nothing has worked.
<Can be a bugga boo! Hope you're going to relate water quality tests... and your investigation of UV, Ozone...>
I didn't have fish in the pond last year and before I got any this year I totally cleaned it to get it ready. Could it be going through some natural process and should I just let it be?
<Mmm, yes>
I only have 4 fish (goldfish/comet varieties) and I lost one of them yesterday. My 2 biggest, one orange and one, a white fantail with beautiful red spots, are acting strange.
<Very likely there are enormous vacillations in pH, dissolved oxygen, even toxins produced via the algal event>
They normally hide either under the hyacinth or at the bottom behind the filter but the past couple of days they are going to the more shallow, upper level, being very still either next to each other or practically on each other. They are so still you would think they are dead. If you go to touch them they will take off very fast, but eventually come back to that spot. I had my water tested and it all looked fine except for a slightly low Ph which I have also been battling this year.
Any help on any of this would be much appreciated.
Thanks!!!
<What? Where's the boeuf? Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
and the linked files above... Bob Fenner>

Copper fountain/water-effect algicide use - 03/27/06
Dear Sir,
I wonder if you can kindly help me.
I have recently purchased a small indoor waterfall, and I wish to prohibit algae growth. Please see link below.
The unit has a solid copper base, which contains the water - someone has
told me that the copper is a good agent to eradicate algae.
Could you tell me if this is true, or, do I need to take other precautionary measures ?
I would greatly appreciate your advice,
Thanks
Steve Davies
http://www.amazon.com/gp/product/B00015D7JU/qid=1143500993/sr=1-1/ref=sr_1_1/103-0412159-4974247?%5Fencoding=UTF8&m=A200W35O5U03O&s=home-garden&v=glance&n=1055398
<Mmm... I would not use a copper-based algicide here... nor the conventional halogen-based chlorine, bromine... too likely to stain, ultimately corrode the unit itself. You might look for Simazine-based "aquarium" algicides (e.g. Algi-gon) or Jungle Pond Blocks (Di-methyl urea calcinate) or equivalent... Whatever you use, I would take care to not have the water splash on, or incidentally be poured on living plant material... and I would frequently (twice a month or so), dump completely and re-fill the unit with
new water. Bob Fenner>

Re: Advice please - 03/27/06
Hi Bob,
Thanks a lot - that is very kind of you.
However, the water containing tray of the waterfall is itself made of copper
- I was wondering if that would be sufficient to prevent the algae.
<Mmm... depending on the water quality, principally pH and alkalinity, very
likely so... Turns out that copper is much more soluble in lower pH and alkaline water...>
I do not understand the chemical make up of these things - would Fountec be suitable ?
<Not familiar with this>
The unit has no live plants - it is only a small decorative unit , with a copper base, water pump, and slate backdrop.
I greatly appreciate your time,
Thanks
Steve


Green Pond Water, ongoing mistakes, lack of info. 9/22/05
I have now carried out three partial water changes, each time changing 3/4 of the pond water, and this has cleared it.
<Okay>
I have however encountered a problem. I have added pond salt and a substance recommended by my local supplier, which I am assured, will guarantee that the water remains clear.
<Not okay... what is this substance? A flocculant? A binder of some sort, an oxidant? What is/are the component/s?>
I now find that one of my smaller koi is in distress. Whether this is because of the action I have taken or whether it is purely coincidental I do not know.
<Me neither...>
Regarding the salt addition I put in one third of the recommended amount for the volume of my pond, as it stated in the instructions that it should be added in equal quantities over a period of three days.
Is there anything I have done wrong?
<A bunch... Bob Fenner>
Regards,
Ken.

Re: green water 9/23/05
Hi Bob,
<Ken>
 The substance I have added is manufactured by Kusuri Products and is in powder form. It is called Eco-Pure and the information on the packaging states that it is a special
<Love that word... and the word "love">
biological powder encapsulating environment friendly beneficial bacteria. Designed as a maintenance product for regular application in any aquatic pond. 100% non chemical
<Is it made of energy and vacuum only?>
and virtually impossible to overdose! The product will bio-degrade [which it has done] and flocculate suspended solids increasing water clarity. Lower nitrates and phosphates inhibiting algae and blanket weed growth.
 It also states that any chemical added is detrimental to good bacteria as used in Eco-Pure.
<But/and you had stated you added salt to the water...>
It is recommended that should any chemical treatment be carried out Eco-Pure is added twice a week for two weeks to compensate for the loss of beneficial bacteria.
 It is clearly stated that it will not kill blanket weed or algae but will assist in resisting their development.
<Yes... an important distinction... >
 It seems perfectly okay and I have just noticed something else on the packaging. It states that it contains Saprophytic micro-organisms, conforming to EC EFB class 1 and have never been described as casual agents in human illness and pose no threat to the environment.
 It does not appear that this was the cause of the problem and the fish seems much better to-day.
<Good>
 I failed to mention that on each of the water changes carried out a de-chlorinator was added as I used tap water. Consequently there should, in theory, have been no adverse incidents from this.
<Sounds good>
 I will be interested in your comments. Ken.
<Please peruse WWM re pond algae control, the linked files there. Bob Fenner>

Pond in serious trouble... poisoned at least by algicide 8/27/05
I have been going to my local pond supply store and trying to get help on
this problem. I would love to hear your advice. First the pond started
getting a lot of green slimy algae. The store said to add barley so I did. No
help. Then after a week or so they suggested adding more plants. So I did no
help. Then the store suggested algae fix, and a white powder that you put on
top of the water after removing all of the plants and letting this powder sit
with the filters off for 20 minutes. This did nothing. Now the pond smells
really bad the fish are dying and I still have both green and brown algae.
You can't walk in the pond as the bottom is very slippery. Do you have any
suggestions?
<... yes... study... What is it about your pond for instance, that inspires such algal profusion? What is your water quality... particularly nutrient levels like nitrate and phosphate? Do you have an adequate biological filter? Circulation? The algicide you've used is toxic, and is killing your livestock... I would start a series of large water changes to dilute this, or move your livestock out entirely...>
I have lost 2 3.5 to 4" gold fish and 3 or 4 small babies. I
don't see any sign of disease,
<... environmental disease, poisoning...>
but I have noticed that all of my fish have
stopped eating. They also seem to be very lethargic. Please send any help that
you can. Thanks
Sissy
<Start by reading here: http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
and the linked files above. Bob Fenner>

Green water in small pond 8/23/05
My wife was having a yard sale, and 2 paramedics stopped and saw green water in my pond, and told her all i needed was some Peroxide and it would clear up, they said that's what they use.....any truth to that?
<Mmm, some... Short term H2O2 can "burn up" free-floating algae to some degree... Trouble is, the nutrients that were the algae can and will (quickly) re-grow... Please read here re algae control in ponds: http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
and the linked files above. Bob Fenner>

CopperSafe... 8/4/05
I sent an email to another address and since I haven't heard back, found this other one from your home page...pretty nifty! You have presented things in a way that is very personal. So, onto the repeat question....
I read the help you gave on your web page about keeping a fountain clean by using Mardel CopperSafe. We just came back from the pet store and are really confused and so is the help there! This is for itch, velvet, and other external parasites for FISH! Is this really the product?
It is that versatile???
Waiting to hear about this one!
Carol
Woodinville, WA
<Copper can indeed be put to good use in such features... Please read here: http://www.wetwebmedia.com/PondSubWebIndex/cuusepds.htm
and the linked files above. Safe... for birds, surrounding landscape... and effective for algae control. Bob Fenner>

Goldfish behaviour 7/4/05
Hi
<Hello there>
I have a very large garden pond - twenty foot by forty plus foot, four feet plus deep at one side, lots of goldish which do breed and so on. However they do this every year and I now feel I need to know why.
They are mostly just hanging suspended in the water, like they were asleep, although they did consent to eat a little yesterday and in the post dawn period they make little bubbles on the surface which linger most of the day.
<Ah, yes>
Can anyone tell me what they are doing and why? No filter or oxygenator alas but I have lived here for more than ten years now and have managed so far okay.
Thanks very much
Angie Watts
<They are experiencing changes in the pond due to the season... in essence being poisoned... changes in pH, mixing of bottom water... You might consider adding aeration, biological filtration... that will make this system overall more homeostatic throughout the year. Bob Fenner>

Re: Pond Goldfish behaviour 7/5/05
Thanks very much for your reply. I found the credit note from the water
company when we had to have the concrete pond relined with a butyl liner as
it had cracked (September 2003) and I found I reclaimed for 35metres3 not
put back into the sewage system.
<A good note... in the States we also can at times realize such a saving from notifying our water/sewage service provider>
Add to that the contents of 2 x 45 gallon
containers, one large fish tank and a paddling pool (for the marginals) I
think that works out a pond approx 7,800 gallons, am I about right?
<Mmm, 35 cubic meters of water is about 9,409 gallons...>
About a
hundred goldfish (although most of them have bred black). I have ordered a
solar powered oxygenator to help things & use barley straw in old tights
(last added about three weeks ago) but I guess 2 and half inches of rain the
other day really upset my systems. Although I have to confess I was in
there the week before taking out some weed! At the moment I am just
spraying the water a little each day to add oxygen.
<All good techniques>
The fish seem to be
okay but after looking through your web site I am resolved to feed them less often than the several times a day they have got into the habit of begging for.
It's a great site - I have learnt so much from looking at it.
Cheers
Angie Watts
<Thank you for your kind words, caring and sharing your experiences. Bob Fenner>

Green Pond, Atrocious English 7/4/05
hi sorry to trouble but could you please help me, i have a fish pond 5 foot by approx 5foot with a filtration system which has a UV filter we have put barley straw in the pond and the water is dark green and you cannot see through the water. the pond is 12mnths old we have changed the UV bulb a couple of weeks ago and this has not helped, any advise gratefully received, thanks
<Please learn to use your spell- and grammar-checkers... and read here: http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
and the linked files above. Bob Fenner>

Very Large Pond Question, WetWebMedia
Hello Bob,
Let me start by saying that I am a huge fan of the "conscientious marine aquarist" book for my 90 gal marine aquarium at home, and of the WetWebMedia website. I thank you very, very much for all the advice you give us there.
<A great pleasure my friend>
We are real estate developers in central Mexico (city Leon, moderately warm climate), and in one development we have a sort of a small "river" with about 300 koi carps in there. The "river" or pond, measures some 400 feet long, one foot deep and about 6 feet wide, with some variations in with up to 15 feet. I estimate it holds some 30,000 gallons of water. It is mostly under the shade of many trees, which also means it gets a lot of leafs and grass in it.
<Yes>
Along the 400 feet, the water starts out coming out of 2 waterfalls, each about 4 feet tall. and then finds another 3 falls of about 1.5 feet along the way. The water currently flows some 10 hours a day, the rest of the time the pumps are shut off. We take out about 5,000 gallons of water every day from this river for watering the gardens, and add the same 5,000 gallons of fresh water (plus evaporation top-off) from a water well we have.
<Good plan, practice>
Every month, we take out about half the water volume and replace it with fresh water, and have a beautiful looking river. for about 2 days. Then the water turns a cloudy brown-greenish. until you can't see the fish anymore. This despite the daily water change.
<Yes...>
We are currently not feeding the koi, as my LFS guy told me they would simply eat mosquitoes, bugs, or algae that grew there.
<To some degree this is so... the fish won't be as robust, colorful...>
I don't have plants in it yet, but I've now read we could use quite a few.
<Yes, definitely worthwhile adding here>
The question is regarding filtration: What sort of biological filter should we use? (an open one, I read. but size? Materials?), mechanical? and, would a UV help, or is it simply too large for one?
<In this size, type system, the plants and ozone would be all I would use... all else are impractical... too expensive to install, operate...>
How many watts would I need?
<Again, I would look into corona discharge type (not UV lamps) from a larger company here. There are a few that make these for industrial applications...>
Can I buy something that large at a reasonable price?
<Would have to define "reasonable"... Again, the plants... lilies, some hyacinths (keep these corralled)... will get you likely 80-90 percent of where you want to be, at low cost...>
I greatly appreciate any advice,
Eduardo
<Glad to offer it. Bob Fenner>

Pond green water problem HELP
I have a 125 gallon pond which gets morning shade afternoon sun, I have water lettuce and water lilies and some parrot's feather for plants,
<Good choices>
3 feeder goldfish in the pond I am using a Cipro bio force 500 filter and 2- 600 gph pumps 1 to work a water fall and fountain for aeration and the other to the bio force filter ( I have a valve inline to the bio force filter to control
<Nice gear>
thru flow of water), I have been treating the green water problem with Algae fix (3 teaspoons twice a week) Eco fix (3 teaspoons once a week) Accu clear (3 teaspoons twice a week)
<Bad ideas... toxic... not useful here>
and just started using barley straw extract last Saturday (1 oz for the first 2 week's per the directions). The test strips that I have been using show everything in the good range except the water is hard. Tuesday I did a partial water change (20 gallons which I left outside in buckets for 4 day's to let the chlorine evaporate),
<Good>
the water is still green I have even put some beach umbrellas over the pond
<Good idea>
to provide more shade aside from a
dye to color the water what else could I try and if a dye is the only answer will it work with the water already green? I live in Northwest Indiana and we have had some unusual warm temps for this time of the year.
<Mmm, am hesitant (almost) but will suggest you look into using an inline ultraviolet sterilizer, some flow through this by one of your pumps... or resolve yourself to seasonal green (algae) water problems. Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pduvs.htm
and the links above. Bob Fenner>

Algae Eaters In a Horse Trough
Hello I have seen several questions about fish in horse troughs but have never seen any of them answered. My question is... Is it safe for the fish and the horses to put the fish in the trough? I have 18 horses and algae is a big problem in their troughs. Thank you in advance.
Carla in Delaware
< WOW! Wouldn't that be nice to just throw a couple of fish in the horse trough and no more algae problems. Unfortunately most pleco's are from tropical areas and require warm water and some aeration. If the water stayed into the 60's then you could try some Garra sp. with a common name of African stone lapping fish. American flagfish would eat the hair algae and take care of mosquitoes too. There are a couple of people catching pleco's in the far South American continent that have found pleco's that actually come from cool areas. These are not yet available in the hobby but the pond people will love it if they ever become available.-Chuck>

Algae/Fish Killer Help
Sir, I picked up your name on ASK.com. I am having trouble with an outdoor fish pond. I obviously put in too much Algicide, and killed all of my fish. Is there any way that I can neutralize the chemical without draining the pond?
<Not practically... most expedient to do a series of massive (tens of percent) water changes here>
I have a 5000 gallon pond, without a drain so I would have to pump it all out into the street. Any help that you can give me would be greatly appreciated. Thank You!!
Jan Shepherd
<Mmm, if there is any change in elevation, you may well be able to siphon the water... better from the bottom, along with mulm... Bob Fenner>

Pleco in pond
I always hear of goldfish and koi in ponds, but never hear of Plecos. I have a 12" long pleco that I think would be happier in my 750 gallon pond than my 55 gallon tank. What would make me not want to put him in there?
<Really just the chance that the temperature would dip below about sixty degrees F. (depending on the species)>
I would think that the pleco would help out with some algae problems, but would he attack my hyacinths and lilies?
<Should leave these alone. A few species of loricariids (Pleco family) are bred, raised in ponds... in Florida, elsewhere... Bob Fenner>

Algae...I think
Have a pond, put in in June, live in Florida. Pond has a bio-falls filter with a skimmer, a two stage waterfall, pond is about 20' X 6' at it's widest and 3'-4' at it's deepest. I have about a dozen comets and shubunkins, largest is about 6", and a lot of mollies. several water lilies in pots, and a few bog plants. Everything has been going well, but over the last couple of weeks I have noticed the water lily pads have been getting smaller and turning yellow faster and just looking unhealthy in general (but still blooming) , there is brown slime on their stems and all over the rocks, and the water, although clear is brownish colored.
<Good descriptions... the lily pad size change may simply be a matter of change of seasons, but also an indication of a lack of available nitrogen... you may need/want to feed your lilies... can be done in a few ways... likely pelletized approach is best here>
 I feed the fish, but only a few times a week, as the weather is turning cooler. I also feed the water lilies monthly.
<Oh! Should have read ahead>
The fish all look and act healthy. Water tests are all within normal limits.
There is limited sun exposure, less than in summer when we had full sun, so I can think of no reason for algae bloom, there is also hair algae coming off the falls rocks which I remove. I have had ponds before and know that they go through seasons but the brown slime coating everything and the unhealthy pallor of the lilies is concerning. Any help you can offer is appreciated.
Thanks
<What you show in your image and descriptions sounds and looks like blue-green algae, aka Cyanobacteria... though it's brown in color here. There are a few approaches to limiting its profusion... Please read here: http://wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
and the Related FAQs (linked, in blue, at top)... consider testing your water and source water for nitrate, phosphate, doing what you can to increase dissolved oxygen, circulation... consider the possibility of adding a U.V. sterilizer, perhaps an ozonizer IF the degree of "dirtiness" bothers you. Otherwise, "normal" maintenance should keep this pest to acceptable levels. Bob Fenner>

Unknown pink substance on rocks near pond
I have a fish pond in my backyard. I have noticed a pink substance on the rocks around the pond. This has a consistency of bubblegum when touched.
When it dries it dries to a white powder-like substance. Can you identify this for me?
Thanks, Donna
<Maybe... most likely a type of algae... but could be a combination of other organisms, mosses, lichens and such... You could tell if you either took a look under a microscope at a bit, or had someone else do this. Bob Fenner>

Algae in pond 30 Aug 2004
I just added two Plecostomus to the pond; all the algaecides that claimed they were plant and fish "friendly" indicate that they are hazardous to people and domestic pets. Well, I know better than to drink from the pond, but my three dogs don't have a clue. <I'm surprised they don't have a fish snack to be honest.> And since they have a doggie door to the back yard, allowing them free reign to drink from the pond if they choose, the algaecides didn't seem like a real good idea. <Definitely understand.> So, I'll see if the Plecostomus can help matters any and hopefully they won't get too big. <About 18 inches when full grown. They probably won't winter in the pond well, you'll need to pull them out.> If they do, I guess I'll be purchasing a tank (don't have one, even as a confinement facility at this time) so I don't have to choose between any of the fish. Do you have any recommendations for any algaecides that are both fish, plant, people and pet friendly? 
Also, I'd like to maybe clean the walls and "vacuum" out the muck left behind but am not sure what the best way to do that would be. Any suggestions there would also be appreciated. There are times when it just isn't effective to "skim" the crud from the bottom of the pond. Thanks
again for your input and guidance. It's been a pleasure having the fish in the pond; I hope to winter them without too much trouble. <Good luck Jamie and keep us up to date. MacL>

Why has my previously clear pond turn green?
I recently built an 11x17 pond that is almost 3 feet deep in a couple of pools and about 1 foot deep on a 4x3 area. I have two 7 in koi and seven 4 in goldfish. There is a waterfall that falls about 1 foot to the first shelf and another foot to the pond. I've got about 20 different plants in my pond with 2 of them being water lilies. My problem(s) is: About 2 weeks ago my pond turned green. There is some string algae but not an overabundance. I have tried a couple of different biological bacteria liquids but still have not been able to clear is up. Could my water be too hot?
<Could be a factor... warmer weather goes hand in hand with algae blooms>
Also I can not keep water hyacinth or water lettuce alive in my pond. Can you believe it?!
<Yes. Happens... some conditions disfavor their growth, presence>
Within 2 to 3 weeks after I put it in the pond or the Bio-Falls, all of the above water foliage turns brown and all of the roots turn black. I have tried plants from 3 different places. I do feed my fish. They get about 1/4 cup of floating fish sticks each day. Do fish need to be fed in ponds?
<Yes, but this is too much... I would cut back to at most half of this amount. This is another factor in your algae growth.>
I had a great supply of toad tadpoles when my pond was first built. But I have not seen any for a couple of months or so. Also, my water lily leaves are extremely small. The largest leaf so far has been about 2 inches across. One of my varieties is a large one also. Thank you so much for your help.
<Please take a long read through the Pond area of our site, www.WetWebMedia.com. It appears that the "bacteria" products you've been adding are doing you no good... and some of your plants harm... You may need to consider your overall picture here: the amount of direct sunlight, water chemistry, the amount of biological filtration you have, the flow of water through it... Bob Fenner>

An undergravel filter for a water feature?
Dear Bob:
I am having some fun in my retirement. I live in So California, and it's dry and hot (Riverside County). To alleviate some of the fire hazard in my canyon I've put in gardens, and for an aside, a pond/waterfall (perhaps 250 gallons) .
<We live in San Diego about half the time>
The pump that drives the waterfall is solar powered, about 10 gallons a minute with a 2 foot fall.
<Neat>
It occurred to me that instead of installing expensive filtration I might use an under gravel filter just like my fifty gallon aquarium. It works. Kinda.
The solar pump is like a sump pump, drawing water from the bottom but on top of a stainless steel screen with a gravel overlay, (about 4 inches of gravel, fairly coarse gravel)
To keep mosquitoes at bay I put in some guppies. Some guppies now number a hundred!
<Do look into Mosquitofish instead... available from "County Operations" for free... better at keeping aquatic insect larvae controlled, relatives of the Guppy (livebearers also)>
The pond is in all day sun, and so I expect the water to be green,( the water temperature runs around 80 degrees).
everything is fine but I would prefer the water somewhat more clear: the depth is about a foot and a half, and I cannot see the bottom. It might just be a seasonal 'bloom,' I don't know as this is just the first year. Maybe some finer sand on top, ( it's like pea gravel), Any help you may offer will be appreciated, because I had so much fun the first time that I'm building another. But this time it's 1,000 gallons with a 14 foot fall off a giant boulder!
<Ahh, much better>
Thank you,
Paul Hoppe
PS Found your site under Thoroseal.
<Worked on and built systems with in-place UG filters... they do work, but a pain to service... and yours being exposed outright to the sun, being small... will likely continue to suffer seasonal algae blooms. Do continue to read through WetWebMedia.com re seasonal pond maintenance and algae control... Adding some floating and submersed/non-rooted plants, adjusting water chemistry (preventing nutrient availability through using filtered water mainly and pH adjustment...), possibly the addition of a small in-line ultraviolet sterilizer, are all appropriate methods for reducing the severity, likelihood of algal blooms. Bob Fenner>

Clams and Green Water
Hello crew<Hi, MikeD here>, I'm having a problem with green water in my outdoor pond, I was
wondering if freshwater clams could help in this matter?<Actually, they just might. The green water is caused by unicellular algae that finds the sunlight and fish waste a perfect growing medium, and this is just what many clams would order if possible.> I have a lot of
fingernail clams in a creek where I live would these small clams help?<First off, it would depend if the creek temperature is the same as your pond temperature. In order to make a difference, you'd need a substantial number, which could present some problems such as 1) what would they eat after they cleared the water, 2) if they starved, you'd then be looking at a substantial amount of decaying animal matter, which could cause a bacterial bloom much worse than your current problem and 3) many native fish parasites utilize clams as an intermediate host, giving you the potential for an outbreak that could, again, be more serious than your current problem.> thank you.<You're very welcome>

Controlling Pond Algae 7/20/04
We have a pond about 1/2 acre in size by 2 to 3 feet deep. How much rock salt and how often to control our algae?
Thank You, George.
<salting a pond this size may not be helpful or even lawful in your area (contaminating ground/water). More importantly, it does not address the real problem causing algae in your pond - excess nutrients. Your best long term solution for this is natural plants to absorb the nutrients year after year. Do stock with attractive lilies and bog plants instead. Reduce fish feeding if you are at all... and have patience :) Anthony>

Brown Freshwater Pond Algae
Our large Koi pond has a coating of golden-brown colored "velvety "algae. To my eye it looks dead, but our pond maintenance service insists that is simply an alternate form of healthy algae. Every reference I can find to brown colored algae describes something much heavier bodied such as kelp.
Is there such a brown algae as the pond man says? Or, am I correct to smell something in the air other than brown algae? Thanks for your help! James Wohrman
<There are indeed algae found in ponds of many colors, sizes, textures... including brown as you describe. Furthermore, most algae can/do change their apparent color depending on nutrient, light and to an extent water quality, circulation dynamics... You might want to remove some of this algae, place it in a good size (one gallon or so) "pickle jar" and add some tap water to about half of its pond water... and see what happens by growing same on a window sill. Bob Fenner>

K Tea, pond algae control, and lessons in human nature
Help!
I have been trying to find out how to contact you via the phone without any luck. The entire web site does not have a phone number which is unfortunate.
<Mmm, actually... as this endeavor is "all volunteer", we don't have the time, flexibility to handle phone calls>
My problem is this: Last year I had someone build a small pond (approx.. 15 x 25 feet, 5 feet at its deepest point, in a bean shape. It was lined with a rubber lining due to the porosity of the soil. After March it starting growing these long and matted tentacles from the bottom. They then began to float but mostly disappeared when I turned on the water fall. I then added gold fish. They are still there. However a haze of green algae has overtaken the pond and I cannot see to the bottom.
<Not atypical>
Reading articles tells me that what I need is K-tea, but it doesn't tell me how much and for sure it does not tell me where I can purchase it.
I live in the Northwest corner of Ct. Please help me.
Jose Orraca
<... do you have a means of filtering this system? Are there live plants? I strongly encourage you to investigate your options further here rather than trying a chemical approach... Far better to avoid these issues through prudent design, filtration and maintenance than risk poisoning your livestock. Please read through the Pond subweb posted on www.WetWebMedia.com
Bob Fenner>

Re: K Tea, pond algae control, and lessons in human nature
Thank you for your quick reply. Actually, I don't have livestock because I am not a farmer.
<... okay, what sorts of life do you have in this pond?>
 It is mostly a decorative pond. The filtration system is part of the waterfall and it worked quite well at removing the floating algae, but the water is still very murky, in spite of the fact that I clean the filters quite often.
<What sort of filtration?>
 There are no plants growing in the pond, other than the algae, primarily because of the rubber liner. I do plan to plant decorative plants around the pond.
<No potted plants... do you have any floating types?>
I have checked the options and in fact the Connecticut Department of Environmental Protection recommended K-Tea but they did not inform me where to obtain it.
As it is, the pond is very displeasing and I may have to drain it and find other ways to improve my landscape, Thank you again.
Jose Orraca
<Please read here: http://www.wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm
Your system is "unbalanced" in general terms... you can seek to "re-balance" it in favor of clearer water through a few methods... trying to selectively poison it with "K tea" is not one of these. Bob Fenner>

Koi consumption of phytoplankton
Hello Bob, John here. I'm not getting much of an algae bloom this year so far, so I was wondering if large Koi will consume large amounts of phytoplankton. Thanks again for your time.-John
<They don't eat any as far as I'm aware... very small/fry ones do consume some. Bob Fenner>

Water Wizard (pond algal control device?)
Dear Sir/Madam. Herewith a link to a product we manufacture that assists with excessive algae control. Use of it will contribute to increased business and larger client base. Regards, Charles Sterzel
www.waterwizard.co.za
<Umm, I see you have "testimonials" on your site. Do you have any actual "test data" that explain "what" your product does, the actual experimental "effects" the device exerts on water? Bob Fenner>

Oxygen depletion from Algae killer - 7/14/03
Hi Bob,
<Anthony Calfo in his stead>
Well, our goldfish are gone except one shubunkin, probably due to that heron, raccoon or the snakes, however the four Koi that we added have survived and are now 6 to 7 inches long and fat! Here is my new problem. We put Algae Fix in our pond and the following day the Koi were lethargic, gasping for air and migrated to our bogs.
<Arghhh... do check the instructions too (dreadful either way if the warning is there or not): a sudden kill of algae/greenwater when water temps are high can cause a sudden and rapid depletion of O2... the decomposition of clotted algae from the product can do the same thing. Dose timing, aggressive water changes and extra aeration are always recommended with such products>
They seem to be struggling a bit. We added salt and a bunch of ice to the pond and they seem to be doing better. My question is, should we move them to a kiddy pool for a while or just leave them alone? Thanks in advance! Jennifer
<I believe its best not to move them. Do a sound water change (siphoning detritus) and be sure to exploit aeration features (never turn any off at night either as is a common habit). We may escape the treatment unscathed. Best regards, Anthony>

Pond algae eaters
I live in Washington State and have a hot tub sized pond with 7 young Koi. I would like to introduce an algae eater and I'm not sure what kind or how many. Thank you for your great service.
<There are a few cold/cooler water fishes you might try... of the minnow family (same as Koi and goldfish)... but if it were my system of this size, shape... in an area that gets this cold, I would look to other means of algae control. Please read here re:
http://www.wetwebmedia.com/PondSubWebIndex/pdalgfaqs.htm
Bob Fenner>

Pond Algae Control
Hello, I would like to get an algae eater fish for my small pond. What would you suggest as I cannot find any articles other than loaches. Would a Plecostomus survive close to freezing temperatures? In my limited knowledge I am thinking some type of cat fish species would do?
Thanks for you help.............. Frank
<Hey Frank, I have heard of people having success with Plecos in outdoor ponds, but I think near freezing would be a little too cold for these fellas. I would avoid catfish, most catfish will grow large and eat any other inhabitants in the pond. Maybe the Dojo Loach to help scavenge the pond, but I think freezing temps would kill these guys too (10-25C). Maybe a different method of algae control is in order, please read below. Best Regards, Gage
http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm >

Removal of clumped algae
Good Morning,
I have a 1500 gal outdoor pond with Koi. My filtration system consists of a Tetra TP3 filter. I have a 25 watt U.V. sterilizer after the filter, as recommended by my local aquarium. My problem is algae is being clumped on my pond floor and sides. 3" thick. When my fish move it totally clouds the pond until the fish settle in one place. My question is this. What is the best way to remove this clumped algae which is on my ponds wall and floor. My water is crystal clear, and the fish are healthy. Please advise.
<Best to scrape, otherwise entangle this attached algal material on a brush and remove... as a means of permanently removing bound-up nutrients... A note: don't be too fastidious about removing all the algae... better to crop it and have it about rather then free-floating types. Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm
Bob Fenner>
John Laurice

Earthen Pond Question
I own 7 acres have a pond 100 ft in length by 65 feet wide. I need Oxygenators! but have a few problems.
<Okay>
1. This pond is in my back pasture and I cannot afford to run electrical wiring for pumps etc 7 acres back so I am wanting Oxygenators.
<As in plants?>
2. I have Rosey Reds and Albino Channel Catfish in this pond already.
3. I have Welsh Harlequin ducks and African Geese who swim in this pond.

4. My livestock also utilize this pond to cool down and drink from although they do have their own water troughs. The animals in question are: Alpacas, Cows, Pygmy and Nigerian Dwarf goats as well as the before mentioned ducks and geese.
<Okay>
I'm wanting something that is along the lines of a wildlife habitat but must be safe and non-toxic to my livestock as well. I can't find any information anywhere that states what can be used as water plants, mainly oxygenators, that won't harm livestock.
Elizabeth Bonin
Bedias, Texas 77831
Grimes County
<Do check with your local wildlife agency/ies... but I would try Hornwort/Coontail, Ceratophyllum demersum here... grown in some areas where you can control it from spreading (if possible). This plant will absorb a great deal of nutrients, grows under a wide range of chemical and physical conditions, is relatively unpalatable to waterfowl, non-toxic to livestock... Please see here re: http://www.wetwebmedia.com/PlantedTksSubWebIndex/ceratophyllum.htm
Bob Fenner>

Cold water algae eaters
Hello,
I'm not sure if I'm going about this is the right way but your website is one of my bookmarks and I think if anyone could help me you can! I own a horse farm in WV (hence cold winters). In our fields we keep several water troughs for the horses. They are all 100 gallons. In one of the many magazines we get (horse related of course) they casually mentioned the idea of keeping fish in troughs to cut down on algae growth. This struck me as wonderful. As well as horses, I am a long time fish lover with three very large fresh water tanks. Sadly they went into absolutely no detail. The troughs are all hooked to automatic refillers and so there is a constant (if not slow) changing of water (my thought was a nice source of air for the fish). My first thought was of pleco's or some sort of small catfish that would be fairly hearty and clean things up nicely. But the more that I thought about it and as time passed I wasn't sure. Have you ever run into a topic such as this? Do you have any ideas. There are a few things I would like to be aware of before I go any further... (I've tried to read up on all of this but strangely can't find a "Fish in Water Trough" book. lol) Things I need to know: In your opinion would this work and be safe for both fish and horses since I do not wish to harm either? I would most likely tank the fish during the winter and so that is to be kept in mind as well. Which fish in your opinion would be hearty enough but not out grow the tanks? Thank you for your time and I hope to hear from your staff soon...

Algal Info. Search
I wanna know where can find information about organismal called pond Mat and Spirogyra. I want to know the habitat, how they live, how they do everything about these organisms. I hope you answer my question, because I have to show a project of these next Wednesday. Thank you.
<Time to do a bit of searching... at a large College library. Please read here: http://www.wetwebmedia.com/litsrchart.htm
re literature searches, then off to see a reference librarian for help with the "how" to find what is known re these algae. Bob Fenner>

Cryptic algae... questions... BGA in lakes
What do you suspect would be the best way to kill Cyanobacteria (blue-green (algae) in a larger body of water, such as a lake, without harming the other life forms in the pond? Is there a way to break down the photosynthetic process, for instance?
Katie
<How big of a body of water are we talking about (gallons?)>. Your best bet is to figure out what is causing the excess nutrients that are fueling the Cyano. Is there any filtration set up on this lake/pond? Maybe add some algae, plants, reed system, to compete against the Cyano. Let us know, Thanks, Gage.>

Moss (Filamentous algae in a new pond)
I am new with the computer and the pond/water fall ownership.
<Lots of excitement!>
My son and I put in a water fall and a 1500gal. pond in the front of our house. It has nine gold fish and two bottom feeders. All seem to be doing well including the various plants. This water feature has been completed for about three months However, I have a big moss problem. This stuff is long stringy and is hanging from the water fall and is all over the pond liner and plants. My oxygenator plants look like a ball of this moss stuff. how can I get rid of it and keep it clear of this stuff? I live in Cincinnati and the pond is on the east side of the house.
<Many ways to counter these pest algae problems. Please read here: http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm and consider what your possibilities are... perhaps more filtration, circulation, pH adjustment, shading... Bob Fenner>

re: Moss (Filamentous algae in a new pond)
Sorry to bother you again. I read the article you recommended and have learned that I need some type of filter in my system. I didn't realize that a filter was necessary for control of the chemistry, I thought that the filter controlled particulates.
Thanks so much for your comments!!
<Yes to having a filter... and you're so correct re its impact on the overall health and appearance of the system. As you'll find, many folks build the filter for ponds first and foremost (it IS that important) and build the rest of the system, landscape around it. Take a read through the many design, construction and filter materials posted on the Pond Subweb: http://www.wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm
Be chatting, Bob Fenner>

Pond Algae Problems
I really hope that you can shed some insight on what I need to do next in my pond. I have 2 ponds, equaling 235 g. of water. I have talked to the aquatics department at the local pet store, and I have gotten no results from all 6 people I have talked to. In my pond which I have had for 2 years prior to putting fish in, I have 3 plants now and only 7 fish left out of 15.
<If these are goldfish, do not add anymore. You have a fairly small pond and goldfish get large.>
The major problem is the algae. My pond gets 85% of the days sun, and I think I have tried everything to control the algae. Here's a list of the products that I have been told to try: Stress Coat (only with new water), Pond Zyme, EcoClear, pH down, Pond Salt, Barley squares, Pond Blocks, Algae Destroyer. I have recently cleaned the pond 4 days ago, and only used the Stress Coat for 24 hours prior to putting the fish back in, and I have used the Pond Block (2 of them), and the Barley Squares, and I have a lot of algae again. The only other thing I have been told to use is algae eaters. My plants are numbered to 3 now, unfortunately, they have not made it through all of the chemicals. Please help me find some type of solution for my problem.
<You will not get any quick fix solutions from me. To me, it comes down to minimizing algae by proper use of plants. You have sun and nutrients, you will either grow plants or algae. All the various bottled product are unable to give you a long-term solution. Do make use of the extensive writings on WWM starting here http://www.wetwebmedia.com/PondSubWebIndex/pdalgcontrol.htm and following on through the blue linked FAQ files at the top of the page.>
Thank you, Gina Goss
<You are welcome. -Steven Pro>

Blanket Weed
HELLO BOB, I WAS WONDERING IF THERE IS A QUICK FIX FOR BLANKET WEED OTHER THEN A FORKED STICK AND A COUPLE OF HOURS TO SPARE? I HAVE SEEN "MAGNETIC GADGETS" THAT ARE SUPPOSED TO DO THE JOB BY BEING PLACED IN/AROUND THE FILTER OR IS THIS A FANCIFUL IDEA? CHEERS CHRIS.
<nutrient control is generally the key (water changes, small frequent changes of chemical filtration media)... and a pond skimmer with a little salt in the water also does the trick too. Anthony>

Algae and their Control in Biological Pond
Dear sir :
We are the marine shrimp farm owner in Thailand.
Having read from your Algae and their Control in Biological Pond we are very interesting.
Especially in your Mechanical Control Method.
Could you please tell me more about your two favorite method.
Now we have the problem of the blue green algae blooms in our shrimp pond and hardly for us to control.
Thanks in advance.
B/Rgds
Pairoj Simaroj
<I suspect you utilize lime treatments in your culture ponds intermittently to oxidize wastes, eliminate disease... and organic fertilizers for boosting food production to your shrimps (penaeids? Macrobrachium?). If you are sure that your current algae problems are due to eutrophication I would strongly advise boosting air exchange by introducing air (as in bubblers) into the deeper parts (centers) of your ponds... and possibly check your alkaline reserve (especially at early morning and mid afternoon... and possibly elevate this (use pH as an indicator)... slowly (with bicarb of soda... calcium oxide... careful here, slowly, if you must)... Do keep an eye on dissolved oxygen, and if the BGA becomes too prevalent, consider moving the ponds stock to another pond system.
Bob Fenner>

Re: alum
Hi Bob,
Well, someone had tried to use alum of some form to remove phosphates from our ponds. The results were not good as we lost several Koi. But in reading I see that alum should be ok if used correctly. What other methods of removing phosphates are available. Is just manually harvesting the best way?
Thanks, marc
>>
In all honesty (what else have I got?) you've hit the proverbial nail on the head. Other than doing what you can to prevent their introduction (design, construction to prevent suspicious run-off from getting into the system, maintenance (no fertilizer overspray, or overfeeding, over, easily-soluble fertilization for "other" photosynthetic life....), using controlled plant growth to "bioaccumulate" nutrients like phosphates and removing them via biomass (okay, no fancy terminology here, trash removal) is the very best (safest, surest) approach...
Be chatting,
Bob Fenner, not associated with the old Weco Corp. who used to sell Alum as... PondClear... and maybe still does.

Re: alum
Hey Bob,
Any recommendations on controlled plantings? We have approx. a 400,000 gallon pond. 1200 Koi, 100 birds, ducks, etc. some run off from grounds fertilizer. Is there perhaps an additive that can be used with the fertilizer to help it settle in the ground rather than run off?
Thanks again, Marc
>>
All sorts... and this is a tall order... the best would be to "shoot" concrete/shotcrete and some sort of supporting wire (like stucco or light cage material) in the basin(s) themselves.. during a drawdown period (i.e. with the water lower...) and contain the plantings there with sand, small grade gravel over their bases... and utilizing a slow release No-phosphorus type fert. tablet food source (if, where desired)....
Alternatively, a very likely suggestion... make an adjunct basin in the way of a shallow "swamp" area to grow sedges (typhaceans... cattails, tules...) and possibly other amphibious true plants for nutrient uptake...
And/or the issue of aeration/destratification to lower bioload, overburden... do you have a compressed air type unit on this feature? I would definitely install one and operate it continuously...
The waterfowl... I'm sure you've heard this, and would hear much more... but try to get rid of as many of these as possible... They're a maintenance and health (yes) risk...
Take a cursory read of the pieces from "Water Feature Design... " I have posted on the site: Home Page for a fresh beginning... some general understanding of your possibilities.
Bob Fenner

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