It was a bad day for goldfish. To back up just a little, we received our Foss science kit last Monday along with 10 goldfish and 15 guppies. Monday thru Friday all was well. This morning though, six goldfish were floating. Two hours later we lost two more. After the kiddos left, the one of the remaining two went as well. I am not much of a fish expert, thank goodness the very knowledgeable lady at Petsmart was both helpful and understanding. Apparently ten goldfish in the itty bitty plastic tanks provided was just too much and my water changes too little. Poor little guys didn't have a chance. The kids didn't seem to notice that the tank was short half its fish this morning, but two observant young girls informed me of the second loss. I couldn't let them arrive to an empty tank tomorrow morning though! So, three new fish are sitting next to me as I type ready to become classroom stars. Wish me better luck this time with less fish (and a small filter for good measure)!