Need experienced thoughts/suggestions on fermentor tank

[everythingforeign]

I'm starting to do some home brews for a local restaurant here in Peru where I live (from Ohio, but live in Peru) and I've thought about using a water tank to ferment. They come with two valves that can be customized as needed. The ones I've looked at are approved by the FDA in that they're air tight etc. as here in Peru people place them on their roofs and to avoid ultraviolet penetration and dust they're supposedly fit. Well, my main concern or question is whether the anti-bacterial layer that it claims to have would affect the yeast? Just seeking anyone that may have experience with this or maybe I should buy the one without the anti-bacterial inner layer that it claims to have?

Any ideas on controlling fermenting temps for lagers and pilseners?

Appreciate any advice!

 

[SnidelyWhiplash]

can you find out what the AB is? there's a chance but unlikely it wouldn't affect yeast or the beer.

depending on how big that is, you might be able to run a cold water bath around it with some piping, or find a way to have a refrigerator cooling line run through the beer