Fishes die: what did it go wrong?

[thanhreef]

Fish Scales2;538259 wrote: What did you rinse the new sand with? 80% new water and all new sand. Why? where you having some sort of issues?

using tap water to rinse
Old sand was mixed between fine & every fine sand. I hate my chalices were covered by powerhead blowing the sand. While re-aquascaping, I think it would be great to replace sand

 

[thanhreef]

Thank you all very much. All corals & fishes are looking very happy. I am about to test water parameters

 

[sree]

Slinky;538114 wrote: there is a strong correlation between stirring sand and fish die, with live rock, etc. the ammonia probably just spiked a few hours and probably got the weakest fish and the rest survived.

I stirred up sand in the last year twice, first time (small one) killed an urchin and starfish, the second one got a yellow tang.

Same incident happened to me too. Installed a new Koralia 4 close to the bottom and it stirred up all the sand. Tangs and angels were dead next day. Clowns, starfish and the corals had no issues.

 

[miami dolfan]

I keep 2 horseshoe crabs in my tank. They constantly bulldose the sand so I don't get heavy buildup under the sand.