BBB Method, 3" Tablets, and Copper Ionizer

Hi,
New pool owner, quite confused, still learning.

I have a 15'x30' regular (non-salt) pool (average 6' deep) and a 7' round spa. Read about the BBB method, just bought a Taylor K-2006 and learning how to use it.

Questions:
- Are the 3" Clorox tablets ok to use through my feeder? http://amzn.to/2kWjOmI
- Do I need to add liquid chlorine? Or are the tablets a replacement for the liquid chlorine?
- Is a copper/silver ionizer like this one http://amzn.to/2kW9zyS a good investment? Or a waste of money?
- May I use hexaborate http://nisuscorp.com/pool-spa/products/poolproof instead of Borax to increase PH? Are their prices equivalent?