nitrite levels

[hudson of sleat]

Hi everybody.
My lad and I are trying to get into Discus breeding. I have kept fish for over 40 years and have successfully bread many a fish, apart from Discus. When I first started with fish back in the 1960's, Discus was a hard fish to keep, let alone breed. Now my lad wants to give it a go and I said I would help.
We are using 4 x 50 English imp gallon tanks. All were prepared as the book says using a non fish starter for the sponge filters. That was some 6 to 8 weeks back. We have done all the regular water changes as required. We have also got some platies in one of the tanks, to try and help the filters along. We have 8 young discus at present which we feed on beaf heart and blood worm. the water changes are done after the beaf heart has been eaten. But every time we introduce them to one of the tanks the nitrite goes sky high. I have even taken 100% of the water out and replaced it with the water out of my own fish tank which was showing zero nitrite. 24 hours later with the discus in it is reading a high nitrite level. I am stumped as to what is causing the nitrite levels to go high, and even more stumped as to what to do.
can anybody help us in this area?
Many, many thanks.
Phil

[Graham]

Hi nitrite is the result of ammonia and ammonia is the result of feedings, the higher the protein levels of the food fed the higher the levels of ammonia given off.


You don't mention an ammonia reading so it sounds like the nitrifiying bacteria that look after the ammonia to nitrite oxidization are well established; Where as the bacteria that do the oxidization from nitrite to nitrate are not yet fully established. The bacteria that do this conversion are typically slow in establishing in comaparsion to the ammonia conversion ones.

So you feed the fish they produce NH3 (24/7), the nitrifiers oxidize it to NO2 and since these guys that do the oxidization to NO3 nitrate are not established you get the reading...what kind of nitrate reading are you getting?


The water does not contain many, if any of these bacteria so changing water from your own tank is just a waste of time. The fish are producing the ammonia and the bacteria in the bio-media are not established enough to look after it all.

You would be better off taking some of your bio-media and adding it the discus tank

[hudson of sleat]

Hi,

Many thanks for the quick reply.

The ammonia and nitrate levels are fine. We are using an api test kit and it is showing a nitrite level of 1.

Will the sponges out of the sump of one of our tanks help bring the nitrite level down.

I thought it only took about 4 weeks to prime a filter.

kind regards

Phil.

[Graham]

No question that using some established media will make the difference...it's full of nitrifiers, both NH3 oxidizers and NO2 oxidizers.

To get a full colony of nitrifiers to be able to handle all the NH3 produced can take anywere from a few weeks up to 12 or more depending on pH, KH, temps, O2 levels, even the type of media can make a difference.

If it's continually runs high even with the addition of some established media, add a teaspoon of salt (any kind) for every few gallons. This will protect the fish from any affects of the NO2

[hudson of sleat]

I'll like to thank Graham for the info he is supplying me.
Many thanks Graham.
regards
Phil

[Graham]

You're welcome,hope it fixes the problem