So I take it you buy all these foods from market rather than LFS. I got a fahak yesterday and so far I'm amazed by them. Love to see him eat crayfish wish I could do that all the time. They cost too much. Would he get parasite/disease if I get him wild crabs from the ocean ??
I buy the food at the grocery store. It's all frozen. I just thaw it when ready to eat. Each is portioned packaged per serving.
If you want to feed crays, you can get marble cray (providing legal in your state) as they reproduce on their own.
As far as crabs, I would just go to market or the store and get a fresh leg here and there. No risk in that.
Variety is key to a healthy puffer... my fahaka gets everything from Snails / Marble Crays / Clams with shell / mussels with shell / scallops / prawns and NLS... just depends on what i feel like feeding her...
As for tankmates, although i don't normally recommend them i have 1 yellow lab cichlid and 1 albino pleco with mine
Actually he said he has a fahak.
as far as feeding SW crabs--I wouldn't think the salt would be good for his internal organs. Go to the produce dept of your grocery store for foods for him. All in the articles I linked you to.