HELP! How to rescue fish from nitrate poisoning

[catwoman]

I have already discussed the background of this situation in the chit-chat section but now I need to know EXACTLY the steps I need to take to try to rescue some fish with severe nitrate poisoning. This is not my tank. This tank is a co-workers tank at work and I am stepping in to help save these fish. Several neons have already died over the last month. Here is the situation: 20gal hex tank, no light, undergravel filter, ammonia/nitrites 0, nitrates over 200ppm (the max color on my quick dip strip!), no partial water changes done for months (don't know how long). Tank contains: 2 neon tetras, 3 danios,2 albino cories. One of the neons looks very pale, is lethargic and hanging near the bottom of the tank. How much water should I change today, tomorrow, etc? I have a few plants to put in. Will I be able to save the neon that is already in poor shape. I know the nitrates need to be brought down slowly but how slow? How many weeks or days will it take to get the levels down low enough before I can transfer the fish to my tanks at home (yes I am kidnapping the fish from this person)?

 

[FishDan]

I've never had nitrates quite that high, but I would say that you don't have to reduce them all that slowly. The only thing that really can be done is water changes. I'd probably change about 50% to start and see what that does to the nitrate levels. Continue doing this until they become more acceptable.

\Dan

 

[The-Wolf]

yup water changes, personally I'd do 75% water change then test the water again.

 

[Flyaway_Firefly]

i would say the same, water changes are a must, atleast 50% but no more than 80%...

save thouse fishes!

 

[catwoman]

I did a 25% change yesterday. The nitrate level this morning was still pegging my quick dip strip. at least everyone is still alive. I will do another major change today.

 

[lucky62]

Large water changes at one time can also be costly , but water changes are the fastest way to remove nitrates , unless they are already in your/ their tap water .
I would do AM and PM water changes if possible for a day or 2[ 25% each ] then do a few daily water changes of 25% until the levels come down .

I would also cut back or just flat stop feeding for a few days .

change 10 to 25% weekly depending on the fish load , forever