seasons...
Yes, it usually has to do with the suppliers... I went to this one store the other week and they keep a pretty good stock... I asked if they had any khuli loaches because I really wanted one to replace the one that just died recently... they didn't have any and she said they were hard for her to get certain times of year. I don't understand it... I think part of it is that the suppliers push certain things different times of year... and sometimes things are just out of stock... I don't think it should happen but it does. At least that's what the suppliers tell the stores, they could be lying but who knows...
How long have you been waiting for it? Did you pay for it already? If it really has been quite a while I would probably find out what day they place their orders and call them the day before it every single week just to remind them, or just ask them if they ask about it every week... Every month most stores get a new list... sometimes things don't show up on the lists so they might not ask for them, but that doesn't mean the supplier doesn't have them... If it really becomes a hassle I'd check somewhere else...