i just added a pair of clownfish and a 6 line wrasse today, they were fine for about two hours and i came back to them and the wrasse is totally gone, i looked around in the tank and i can't find him. i have a lid on the tank and i checked the chambers in the back and i didn't see him. I also looked around on the outside of the tank to be sure. has anyone else had to deal with this? thanks