Me and my clown killed my tang

[tang named junkyard]

Last couple of days my clown fish uprooted about 1/3 of my 10 year old sand bed. I didn't really think much of it. Friday I went down and bought a tight fitting plexi lid to keep the evap down. My yellow, which was a perfect specimen went from eating great, acting normal to eating yellow polyps and dying within a couple hours. I thought, that's weird. I brought out the test kit and saw the ammonia levels were up. Everything else looked ok. I'm thinking that the sandbed + the low oxygen exchange caused a spike that finished him off in such a hurry. The SUPER downer is he is lost in the reef and the only way to remove or even see him would be a complete dismantle of the reef. I threw some ammonia detox in to try to bring it back down and I'll keep the lid off to see if I can bring balance back. I also sank the skimmer cup as low as I could to get more content out of the tank. I'll back off the feeding a bit and keep an eye on ammonia. Will carbon remove ammonia? Everything else looked good as far as testing.

[Sk8r]

You don't really WANT to stop evap on a marine tank: do your weekly water changes and it will export the extra minerals, if any. Just use a jump shield screen to keep your fish in the tank. You want as much evaporation as possible to keep your temperature from spiking and to help gas exchange: you may have had a ph shift---operating a litltle like what happens when you open a transport bag that's been closed for several hours. That enables any safe ammonium in the water from fish waste to make fast change into deadly ammonia. The sandbed kickup, releasing all the semiprocessed waste from that, plus the lid, as you say, may have been the double whammy.

So sorry to hear this. The reef is digesting the lost fish---that's the other cause of ammonia. It should settle on its own, but you may want to put the clown in clean salt water in your qt until it does. Don't feed the tank for several days until that level goes down. Amquel or Prime can remove ammonia safely. Carbon will remove organics, which might not be a bad thing, either.

[thor109]

Sorry about your loss
I would make my decision based on how big the tang was and how good of clean up crew I had
I would try and find it. I guess in my tank I can move rocks and gain access to any area.