I turned on the other filter and it was putting a very light ripple across the surface of the water to help keep the film from building up. My ph went up to 7.3 and I am running 2 bubbles per second (Was around 6.8-6.9 with only the one filter). I pointed the outlet down so it did not disturb the surface and the ph still stayed up. I have turned off the secondary filter and the ph is down to 6.9. If I just run the one filter and a powerhead, is this going to push the ph back up again? This is starting to drive me nuts.