Watching the 200ltr, I became aware of two of my neons doing a kind of zig-zagging sort of dance, which lasted all of about 20 seconds. Five minutes later, I approached the tank and these caught my eye; They were scattered in the sand. I used a turkey baster to remove them and placed them in a small container with a drop of Liquifry and an almond leaf. I've placed their container in the 120ltr. Looks like I'm going to be super busy.