Drat, I typed out a huge long response and didn't post it! OK, short version. Bubbles down from 6/min to 3/min after 3 1/2 weeks. Algae on ramps, even after mild scrubbing with toothbrush, is keeping bubbles from moving down entire path. (Had to stop ferts for medical treatment, giving algae a foothold) PH effect 1st week 8.0 drop to 7.4 on 3rd day, 7.4 on 7th day, no test 14th day, 7.7 21st day. Plants still bubbling almost as much as before however, a few fine bubbles from plants directly under light bulbs.
Comparing that to DIY yeast with a gelatine recipe, initial rate is much more bubbles per minute, but I think that was air from the bottle, now it is making 2 or 3 bubbles a minute, hard to say because it is a stream of minute bubbles that lasts for 10 sec then stops for 20 sec. PH effect on 3rd day was 8.0 drop to 7.4 in tank with homemade reactor, 8.0 to 7.8 on 3rd day for airstone free below power filter outlet. In each tank, I see some fine bubbles from plants, however. Some snot on each airstone probably hindering response, need to make bubble counter, this weekend.