Green Water

LRPRESTO · Mar 13, 2007

Hi! How do I get rid of green water? :sick:

It has gotten so bad I can hardly see my fish! I have tried changing the water (50% of it) and now it is worse than ever. I have a 45 gal. tank with three big gold fish in it. (It cycled for almost a month before I put the fish in) Advice would be greatly appreciated.

Puffdaddy · Mar 13, 2007

You have an algae bloom(very common). There are many water additives at your lfs that will solve your problem.

How long do you keep your lights on? You may want to reduce the length on time they are on.
Is your tank near a window or in direct sunlight? This is a big cause of algae blooms as well.

celaeno · Mar 13, 2007

there are many ways to get rid of green water. the most effective ways are diatom filtering and the use of a uv sterilizer. check out the green water section of my site for other methods.

i also have green water in both my tanks, but hopefully the 9w internal uv sterilizer i bought will take care of that. you can buy one from petsmart's website.

dee dee · Mar 14, 2007

A 9 watt uv sterilizer on a powerhead with a water polisher did the trick for me in about 4 days.

I tried all the 'home remedies' first. Just a futile month.

I paid about $60 for it.

Hope it clears soon.

LRPRESTO · Mar 17, 2007

Thank you DeeDee, I am curently looking for a 9 watt uv sterilizer now. The LFS told me to cover the tank because if the algae doesn't get light it won't grow, but I feel bad for the fish having to be in the dark all the time! Isn't that bad for the fish?

LRPRESTO · Mar 18, 2007

Celaeno, your site is very informative! Thank you so much for the link to it! The whole willow tree branch thread is very interesting. I sat here and read the whole thing. I must rest now, my eyeballs are all dried out from the "zombe gazing" I have been doing! :blink:

Thank you again! Lisa

edgun88 · Mar 18, 2007

leave your room dark for a day and then do a water change.

celaeno · Mar 18, 2007

LRPRESTO said:
Celaeno, your site is very informative! Thank you so much for the link to it! The whole willow tree branch thread is very interesting. I sat here and read the whole thing. I must rest now, my eyeballs are all dried out from the "zombe gazing" I have been doing! Thank you again! Lisa

if you do use the willow tree branch method, make sure you take the branches out as soon as any of them start to rot.

if you don't and your fish come in contact with them, they will most likely get a fungal infection. my female betta did and she died from it.

gpgscott · Mar 18, 2007

Yes the UV sterilizer will kill single cell algae and as has been mentioned if you are going this route you MUST also use either a diatom filter or a cannister with a micron cartridge. The reason you MUST do this micron filter is that the sterilizer will kill the algae which if not removed will just decay and fuel the next 'bloom'. However none of this is necessary. Single cell algae require three elements, warm water, excess nutrient in water, sunlight. Our aqauriums are warm because they have to be, without light we cannot enjoy the fish, the key here is control that amount of nutrient in the water. Unless you have live plants which require food the ideal state of the water for the fish is no nitrate, nitrite, or phosphates. I have kept fish for over 25 years inside and out and have never had a 'bloom' in an indoor tank. I'm not saying do not invest in the equipment, I am saying that the equipment can cover poor practices and give the illusion of good water quality. Scott

celaeno · Mar 18, 2007

if you need a diatom filter if you have a uv sterilizer, why not just forget the uv sterilizer? isn't having both overdoing it?

gpgscott · Mar 18, 2007

Yes good point, the diatom or cannister filter with micron cartrtige will remove single cell aglae. As I said I don't think the sterilizer is the appropriate way to deal with algae do that with water managment. The benefit of the sterilizer is it kills bacteria which can infect fish. Scott

LRPRESTO · Mar 22, 2007

OK, so I kept the tank dark for about four days and it looks much better (still some green in it but at least I can see the back of the tank pretty well now) I checked my ammonia(.25), nitrate(10) and nitrite(0) levels and they look better than they did a week ago.(last week they were ammonia(1.0) nitrate(5.0) nitrite(2.0) Could this be why the tank is clearing up some? I also talked to the LFS people and they said "do not do water changes, that will make it worse" You think I should tho? I don't understand why it would make it worse if you are getting rid of some of the algea bloom. Wouldn't that make it better? Would it help to put an algea eater in the tank? What will stop it from comming back over and over again? I am afraid to put the light on for fear of making things worse again.

celaeno · Mar 22, 2007

the only living thing i know that will eat green water is daphnia.

rdd1952 · Mar 22, 2007

gpgscott said:
Yes the UV sterilizer will kill single cell algae and as has been mentioned if you are going this route you MUST also use either a diatom filter or a cannister with a micron cartridge. The reason you MUST do this micron filter is that the sterilizer will kill the algae which if not removed will just decay and fuel the next 'bloom'. However none of this is necessary. Single cell algae require three elements, warm water, excess nutrient in water, sunlight. Our aqauriums are warm because they have to be, without light we cannot enjoy the fish, the key here is control that amount of nutrient in the water. Unless you have live plants which require food the ideal state of the water for the fish is no nitrate, nitrite, or phosphates. I have kept fish for over 25 years inside and out and have never had a 'bloom' in an indoor tank. I'm not saying do not invest in the equipment, I am saying that the equipment can cover poor practices and give the illusion of good water quality. Scott

I have successfully used a UV Sterilizer on 2 tanks running straight off a powerhead, not filtered at all and there weren't any problems with decay or another bloom. Also no huge ammonia/nitrite spike as some people warn against. The water cleared and stayed clear. Here is a thread showing photos of the second tank I used it on. I had already used it on my 75 gallon. It was so cloudy before hand that I could not see half way to the back of the tank. After only 24 hours, it was almost crystal clear and has remained so since then (this thread is from 2005). When I moved it to my 29 gallon, I decided to document it with photos. The 29 gallon took a couple days longer but has been fine since also. Both of these tanks were newly cycled which is when you are most apt to see the green water syndrome.

esquirette2007 · Mar 22, 2007

Cut back feeding your goldfish. Algae blooms when there are unused nutrients in the water.

I got a bad bloom when I'd neglected water changes when I was in a car crash. Couldn't afford a sterilizer. I cut back to only feeding in the morning & did lots of water changes & it finally got better.

Higher plants (regular live plants) will out compete the algae for nutrients, too. You could put a bunch of live plants in there. Your fish will munch on them, but you could get a big bunch of floating plants like anacharis (not duckweed - it will clog your filter). They look nice and the floating plants will get the light instead of the algae, too. Then the plants will use up the extra nutrients, which will starve out the algae.

If your tank is getting direct sunlight, you may want to move it, unless you decide to go for the UV sterilizer, I suppose.

Oh, and brine shrimp & rotifers will use up the greenwater like daphnia will, if you could keep them alive in the tank with your goldfish somehow.

Best,

KK