Go to Wal Mart and get a liquid pH tester in the pool or fish section. It will do for now, but eventually you will want an electronic one for ease. I would say if you added a half a cap to a bottle and a half of water, your pH is probably way below 5.5. Don't get hasty, take your time and do things right or the end product will suffer.
dejayou30 Reviewed by dejayou30 on . Soak rockwool without knowing PH? Is there any way I could soak rockwool without knowing the PH is 5.5? For instance... is there a bottled water company that has a PH of 5.5 ? Rating: 5