vitamins , what to use?

[i of the storm]

That's about it: vitamins , what do you use, when & how? I'm hoping to keep garters on a fish diet, and avoid rodents.

[adamanteus]

Your pet store will carry a range of vitamin supplements specifically formulated for reptiles. I think they're all pretty much as good as each other, but let price guide you. A calcium supplement in the form of powdered cuttlefish bone is also a good idea if you're not going to be using whole prey animals. A light dusting once a fortnight should be sufficient.

[Snaky]

Depending on the kind of fish you give, vitamine B1 is needed everytime you feed fish. You can read this article about thiaminase which causes vitamine B1 deficiency and about which fish have it and which don't:
http://www.thamnophis.com/caresheets/index.php?title=Thiamin,
Like James said you can also add some Calcium with it. It's interesting to give it with new-borns and pregnant snakes. If you don't give whole fish, it's necessary each time.

I would not use a general vitamine supplement every feeding, just about every 1,5 month or so.

[adamanteus]

A word of warning about fish containing thiaminase.....
Thiaminase is a cumulative toxin, it builds up in the snakes' body. Giving a B1 supplement will not counteract the effect of thiaminase. Thiaminase destroys B1 (thiamin), making it impossible for the snake to synthesize the calcium in it's diet.
The only truly safe method is to not use fish that contains thiaminase. At all.

[i of the storm]

the petsmart nearby carries rosy reds (made sure thats what they were last night) and Im off to a local petstore tonight (that actually sells snakes, petsmart does not) to get a tank and talk to someone local. I was also going to try fish strips. I should eat more fish anyway.

With all the great info written on this site, plus the personal expert advice, I'm reading as much as I can. so much diffenet than when I was a kid and the local library had one 15 year-old book on any subject I was interested in.:D