Nitrates out of control. Please Help

[tcwoodrn]

I have a 90 gallon tank that has been running for around 5 years. I recently was overrun with hair algae and had to remove all rock, light starve, and replace it back in to be green hair algae free. I believe that the source of my problem is nitrate level. It looks to be between 100-120. I water change about every 10 days and I change about 15-20 gallons each time. What can I do to get rid of these nitrates so that my tank doesn't become overrun with algae again? Everyone I've talked to at my LFSs says that the key is water changes but says that I am doing enough of them. Clearly that is not the answer, or I am doing them wrong. I've read about Right Now bacteria and carbon treatment but it confused the hell out of me. Can someone please help me?

 

[rebelprettyboy]

Have u been checking ur water before adding it to ur tank?
Whats the stocklist in this tank?

 

[koesterkep]

Tough call for nitrate removal. You could lookinto vodka dosing as well as adding a nitrate remover but som e do not work that well and the ones that do are quite expensive. Zeo does a great job add killing the nitrates and ammonia but is a little costly. I would recommend adding more cured live rock if possible and maybe some live bacteria.

 

[florida joe]

First let me say I sympathize with you. And now for just my opinion. The first thing to look at is how nitrates got into your tank. Obviously one-way is nitrification of ammonia. A necessary process. The second is introduction through your influent water changes. Which I am sure you checked. Do you have a refug? Are you using some sort of algae filter with caulerpa? Caulerpa stores nitrates it does not turn them into nitrogen gas. When it dies it dumps massive amounts of nitrate into your tank. But you could have an on going die off as caulerpa changes from one form to another. Do you have a red slime out brake? It also stores nitrates. And gives it up when killed. As far as live rock. We must understand that denitrification happens deep with in the rock at a slow pace. Live rock denitrification is a very small-added benefit we receive by adding it to our tanks. As you know water changes lower nitrates by removing water high in nitrate and through dilution by adding nitrate free water. It is only a stopgap. Not a cure for its build up. So where does that leave us. If you rule out all of the above. Then nitrates can only come from. The introduction of ammonia into your tank on an on going basis. Are you over feeding? Do you have an on going problem with fish disappearing, perhaps dieing and going unnoticed, and decomposing?
The high numbers you are getting with your nitrate test in a 90-gallon tank IMO would support a high and constant introduction of nitrates into you tank other then through natural nitrification. IMO your may be seeing the sum of a few causes I would start at introduction via water and work my way down the list

 

[tcwoodrn]

I recently removed the bio-balls from my sump and replaced them with live rock. Does anyone have experience with this? I was told by several different LFSs that bioballs store nitrates. I also did a large water change. I have really cut back on feeding in the last month and feed them 1 cube of frozen food per day along with a quater of a sheet of algae for the tangs. I have 6 fish, (6" blue hippo tang, 3.5" yellow tang, 4" maroon clown, 4" pink shrimp goby, 1.5" pajama cardinal, and .5" yellow tail damsel). I also have a green brittle star that is about 18" tentacle to tentacle and hundreds of crabs/snails. I am planning on adding another larger tang or rabbitfish in the coming weeks. All help is vastly appreciated.

 

[cjworkman]

cutting back on feeding will probably do it.
I feed 3/4 of a cube of frozen food a day. (half in morning, half at night) for 1 5" yellow tang, 2 2.5" clowns, and 1 5" wrasse. I also have a large serpent star and a Green mandarain (but she only eats live food).
If you were feeding signifigantly more than 1-1.5 cubes a day, you were probably over feeding.
Also, you have to remove uneaten portions of the algae sheets. If it hasn't been eaten in 6 hours it should be removed.
Also IMO, 2 tangs is already too much for a 90... don't add another. Each tang needs a signifigant amount of territory.
Let the nitrates come down slowly.. anything that changes quickly is worse than have poor water quality to begin with.

 

[florida joe]

Originally Posted by cjworkman
http:///forum/post/2669297
cutting back on feeding will probably do it.
I feed 3/4 of a cube of frozen food a day. (half in morning, half at night) for 1 5" yellow tang, 2 2.5" clowns, and 1 5" wrasse. I also have a large serpent star and a Green mandarain (but she only eats live food).
If you were feeding signifigantly more than 1-1.5 cubes a day, you were probably over feeding.
Also, you have to remove uneaten portions of the algae sheets. If it hasn't been eaten in 6 hours it should be removed.
Also IMO, 2 tangs is already too much for a 90... don't add another. Each tang needs a signifigant amount of territory.
Let the nitrates come down slowly.. anything that changes quickly is worse than have poor water quality to begin with.
Certain changes should be undertaken slowly, temp, salinity for example but IMO nitrates are not one of them and they should be lowered or eliminated as quickly as possible if they are at an unsafe high level