Does anyone know much about them? We have a 240lt tank and up till now they have been pretty good but I've noticed over the last couple of days they don't seem to be eating as well as normal. Normally they absolutely devour bloodworms but I noticed this morning there seems to be a lot not eaten. Also one of the bigger babies is darker in colour and not well as is spinning himself around. Not the slow spin of a dying fish though and he still seems very mobile. I'll change the water and clean the filter and race out and get some Melafix but if anyone can give me some pointers, I'd appreciate it.