Question
I had to drain my pond to repair two cracks. Since refilling, I cannot get Nitrites down below 0.5 ppm (1+ week ago). Amonia is at zero. Tested tap water used to fill pond. It tests almost 1 ppm!! Anything I can do to get the fish back in the water?

Also getting what I would assume is brown algae (can't find pics anywhere on internet). Never had this before since pond gets a good amount of sun. Any specific control for brown algae?

Thanks,
Frank

Thanks,
Frank

Answer
If your tap water is testing positive for nitrite, then that is the problem.  You may want to get another test kit of a different brand to verify that the test kit is accurate.  Your biological filter once established can normally deal with some nitrite in tap water.  In the mean time, you can add good bacteria to the water and some pond salt which makes nitrite less toxic to the fish.  You can also try to filter your tap or pond water through active carbon to remove some of the nitrite.

Brown algae are diatoms and look like a brown film on things that should wipe off easily.  Brown algae like low light levels.  I wouldn't expect brown algae to hang around an outdoor pond for long so it shouldn't be a problem.  Snails and other algae eaters may eat it.  My page on algae is at http://www.fishpondinfo.com/plants/algae2.htm but the methods for green algae aren't all going to work for brown algae.

Good luck!