theyammieguy
Active member
Why is it necassary to have biological filtration in a QT tank? I've read where you need a seeded sponge or whatnot from your DT tank as a filter.
Why do fish need this?
Why do fish need this?
QT question
- Thread starter theyammieguy
- Start date
wooden_reefer
New member
Why is it necessary to cycle the medium for the DT?
The same reason you need to cycle the medium for QT. Ammonia is toxic to fish and massive WC in QT is PITA and expensive. Not obvious?
I guess may be yours can be a good question.
Fundamentally because some drugs (and hypo gradually) that are very effective against some pathogens do not affect nitrification bacteria significantly. Copper or hypo , and many drugs against the larger external parasites, do not affect nitrification very much. With these drugs, you can have nitrification confidently.
Antibiotics as a class will affect nitrification to various degrees, managebly mild or gravely destructive. It is a good idea to be able to remove the biological medium from the filter , and set aside, when you have to use some of these drugs. Sometimes even with these drug trying to manage to get by is often a good idea. Neomycin tends to yield some nitrite but not much ammonia; nitrification struggles but may get by.
Do you enjoy 8 weeks of water change in QT? WC in QT without nitrification is more demanding than WC in the DT: much more massive and often is needed because ammonia, unlike organics and nitrate, PO4 etc, is acutely toxic. You generally cannot just change 20% water in a QT. 0.4 ppm ammonia is not much less toxic than 0.5 ppm.
Add, do not just seed a sponges in Dt and then use in QT. The medium for QT should be deliberately cycled. You often will still have ammonia in QT if all you did was robbing from the DT. Rather, rob just the seed from DT, then cultivate more bacteria deliberately for QT. You will be much more confident that there will be enough bacteria for QT this way.
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theyammieguy
Active member
Good explanation. Thanks.
