nitrates are high

Question
QUESTION: ok,i have a 55 gallon tank. i cycled it for 3 months with
used filter medium from another tank thats been set up for
years. iv'e recently (about a month ago) added a blackbelt
cichlid and 3 electric yellow africans to the new tank.
before i put them in the nitrates were slightly high,but not
in the danger zone. since then the nitrates have turned to
the danger zone and wont go down. all the other levels are
ok. iv'e done plenty of water changes, and checked my tap
water itself and its zero for nitrates. all anyone can tell
me is that i should do water changes, but its not helping
and i cant add real plants because the blackbelt will
destroy them. also there is alot of brown algae growing fast
in the tank. i clean it off and in two days its back. also,
one last detail, a pleco and two previously purchased
africans have died shortly after putting them in this tank,
but the three i have in there now and the blackbelt all seem
fine. i dont know whether the nitrate problem is causing the
deaths, but i really dont want to lose anymore fish
especially my blackbelt i love her. can u help me? is there
anything i can do? by the way, my other tank doesnt have any
of these problems other than green algae. please help if you
can, i would appreciate any knowledge you can give on this
subject. thank you.

ANSWER: Hi Katie

If the nitrates were slightly high prior to adding the fish to the tank, the tank had not completed its cycle yet. The myth that tanks complete cycling in 4-8 weeks is not necessarily true. Some tanks can take 4-8 months or longer to cycle. Following these steps should help you with your high nitrate problem until the tank completes its cycle.

Feed your fish no more than they can eat in two minutes. You may want to reduce feeding to a small amount once a day, or every other day until your nitrates come down and stay down.

Vacuum the gravel thoroughly to remove excess food and fish waste. Waste collects in the rocks, so you need to use an aquarium vacuum to clean the gravel. Also, clean the interior tank walls and decorations. This should be done once a week with your water changes.

Clean your filter(s) and replace your filter cartridges. Excess food and waste can get in the filter cartridges which will raise the nitrate levels. Replacing the cartridges once a month will lower the nitrate levels and increase the oxygen level in your tank. You may also want to add an airstone in your tank to increase the oxygen level.

As you've heard already...water changes. 25% water changes must be done once a week in any tank to keep fish healthy and happy. In tanks where the nitrate level is in the danger zone, you should do 10-15% water changes every few days. Retest the water 24 hours after each water change. If levels are still high, do another 15% water change and retest the next day.

Brown algae is common in newer tanks that have not cycled yet. Keep it under control by using a good aquarium scrubber. Do not use any soap or chemicals to get rid of it as this will kill the bacteria in your tank and prolong the cycle process.

Hope this is helpful to you, good luck!

Richard

---------- FOLLOW-UP ----------

QUESTION: thank you,but if you say the tank hasnt cycled yet then wont
changing to all new filter medium make the cycling process
take longer? and i already only feed them a small amount
once a day and vacuum with every water change.im sorry, im
just so frustrated, and thought with three months worth of
cycling with the other tanks old filter medium that this
wouldnt happen. i guess ill be doing alot of water changes
(ugh), but was wondering about the new filter cartridges.

Answer
Hi Katie

Perhaps I wasn't clear and for that I apologize. You don't change out all of the filter media, just the carbon cartridges. Carbon cartridges over a month old will lose their effectiveness and become useless. You may want to cut back feeding to once every other day until your nitrates are under 50ppm.

Hope this helps, good luck!

Richard