Nitrite and Ammonia levels

[imajica]

I have a 10 gallon (37L) Biube which is home to 6 Neon and 6 Glowlight Tetras and about 8 platy fry(only 3 weeks old). The tank is now 8 weeks old and had been cycled but now I am showing signs of Ammonia and Nitrites.
Ammonia = 0.25
Nitrites = 0.50

I am doing 15 to 20 % water changes everyday but the levels don't seem to be coming down!!
The fish seem fine, feeding ok but not that active the rest of the time, just seem to hang in a shoal.

Can anyone help?

 

[DaHerb_what_herb]

were the fish added to the tank at the same time if so it might just be that the tank wasn't quite ready to handle that many new occupants.

my advice would simply be to continue to make water changes as you are until the levels balance out at 0 again.

 

[rdd1952]

I would say you are overstocked. That's 12 fish (24" and not counting the fry) in a 10 gallon tank. You may be ok if you are heavily overfiltered. As DaHerb_what_herb said, if you just added more fish, that would be the problem. A tank is only cycled for the fish that are in it. Any time you add more fish, you start a mini cycle until the bacteria can catch up. If they have been in there all along, I'd say that the filter isn't adaquate to handle such a heavy fish load.

 

[Fish 'R' Fun]

Keep going with the water changes, you may notice a change over a period of a week or two. As for filters, i would upgrade to a more powerful one or a larger tank.