After saying that I am quiting the hobby and selling all my fish and my 150 gallong tank, I decided to keep my qt tank (45 gallons) and put some small fish in there and a few inverts. No one would even make a fair offer on my 375 gallon tank and giving it away is not the way to go for me so if work picks up I might get it up and running, any way I have bought snails (turbo) twice now and they die off the very same day. The first 2 I didnt accl. so I thought that was the problem, but the four I got yesterday I accl. for aleast 1 1/2 hours and they were all dead this morn. I am using sand and rock out of the dt that I sold and I did use copper in there and I did test this tank and according to my test kit it doesnt show that I have much if any copper in the tank, my hermit crabs and my horseshoe crab are fine so what do you think? Is there still enough copper in there to kill them?