Ammonia

[Coy^0^te]

Hi, I need help! I have a 55 gal. reef tank...3" live sand, 50 lbs live rock, four fish, crab, brittle star, shrimp, several lps corals. 350 watts of lite, skimmer, calc reactor. Everything has been stable for three years. I do 10% water changes every week.
Last Sunday I did my water change. Later I noticed the corals were not opening as per normal. The fish were and are fine. I started testing and my fastest kit shows .4 parts ammonia. Nothing has died. Anyone have any ideas about cause and/or cure?
Thanks,
Sevendog

 

[monkeyboy]

Thats really frightening, with a thick sandbed and 50 pounds of rock the only way you could have ammonia is because the nitrification cycle is being interrupted. Check the dates on your kits too, they could be old and the corals closing up a coincidence. If there is ammonia in there i would start off w/ large water changes and figure out if your doing anything different than usual which could be screwing up your bio-filter. HTH