Try your local pool store they should carry 12.5% with the price
per chlorine equivalents cheaper than most, plus you lug around and pour less. Just be prepared for the "why liquid you'll raise your TDS"
Well, that can be a bad thing. I think you possibly have misunderstood TDS. TDS is an irrelevant parameter for a pool so can be ignored.both my cya and CH are a bit low at the moment