All my turbos died off in a week (6 each) . So I checked water water, (PH, Nitrite, Amonia, Nitrate, Calcium) PH is low at 7.8, but everything thing else good. Waited a couple weeks and started getting alot of algae, bought 12 more turbos died within 3 days, water conditions the same. Never had a problem with turbos since I started my tank, (4yrs). I've been having problems getting my Ph back up, also a new problem. Any ideas on the culprit?