The sheep meds will be the same thing. It's actually a livestock wormer. Lol. The avitrol comes in liquid and pill form. You want the pill. The liquid has glucose and will cause massive bacteria blooms.
http://www.aquariumlife.com.au/showt...-found-in-fish
A bit of a read but heaps of good info.
Do you know if it's safe for loachs as apparently they're not up to withstanding most medicine and also how do you work out how much to give them if it's for birds? And does it actually kill them or do you need to vacuum them up as they fall out only half dead (as I hear most medicines do)