6.8 on peat moss will not work, that's for sure! i only grow in peat moss, and 6.8 would be too high in actual 'real' soil, in peat moss, it's a disaster. In any case, happy growing to all, i will help others. i push 6-8 oz plants with 400 watts of light using only gh flora micro and bloom with epsom salt at times, if my ph going in was above 6.3, by the time flowering comes, heavier elements like iron, copper, zinc, manganese will start getting locked out, only remedied when i lower ph below 6. It's not just me, if you look at research papers from studies conducted with sphagnum peat moss, they all agree with what i say..look at even how pro-mix (same ingredients) advertises their product..ph between 5.8-6.3! Alot of people get confused as when they see 'dirt', they automatically think, oh, that's soil..yet it has a very low cec, so what makes it soil? It's not, it's considered soilless, and ph should be adjusted accordingly. In any case, like i said, i won't try to convince someone that 1+1=2, if you guys say its 3, then go for it, good luck!