Can I use a bucket as a chiller for a 14 gallon bin?

DWC in 2x 14 gallon bins with one plant per bin. I don't want to recirculate both with different strains and as a newbie so I'm thinking of using a 5 gallon bucket for each bin so they have their own cooling. I'm just using frozen bottles as a cooling method with a fan blowing cool fresh air in between the bucket and the insulation that's wrapped around the bucket to help.

Before I put this together I just want to make sure that it'll work. There's going to be a lot more water in the bin/main res then what's in the bucket. Won't it back flow or overflow? Or will it just stay level between both the bucket and the res?

Anytime I look at any diy recirculated DWC it's usually a completely different setup then what I'm asking here? I just don't want 10+ gallons of water pouring over?..

The best thing I've found when putting together systems of multiple tanks and reservoirs are float valves. They're cheap and precise and super easy to install, and all the adapters, tubing, etc. can be found at a big box hardware/supply store. This prevents any back-flow or overflow you might encounter. Just install a little float valve on each of your DWC bins and connect the tubes to your reservoir, potentially using a manifold (or multiple T's) so you aren't poking tons of holes in to your main res.

So you'd just recirculate each DWC independently and feed them from the main res... best I can gather from your description, sound about right?

Amazon has loads of options, I use the Kerick brand listed at the top: http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias=aps&field-keywords=float valve

Not sure what your question is regarding using a bucket as a chiller. Sounds like you're just using water bottles? Are you trying to use a single chiller on your main res? Or are you just trying to determine how to rig it all up?

Edit: A caveat regarding float valves. They need some pressure to flow effectively, so if you want to fill something up fast, you'll either need a pump in your main res or lift the res significantly higher than the DWC tanks. I have an RO tank that passively tops up my res. It sits a few feet higher than my res, and takes almost an hour and a half to fill up 15 gallons. I placed a pump inside and now it takes 5 minutes.