How come the Ph will change?

[MisterE]

Look at the tubing that goes from your aquarium pump to the air stone.. EVEN after 1 ciggie that thing will have tar in it... yikes...

I smoke now and again.. YET i maintain KAK diesel status...lol.. lots of running, frisbee, poongazing, dead lifts.. etc....

I know that a sulfur burner with airstones running is a major NO NO..

I don't know exactluy what ciggies do.. but I don't recommend it.. or if you do do it.. put a PH tester inthe reservoir and report back to us..

iloveyou

I do use a continuous PH/TDS meter and before my latest res change, my PH kept dropping pretty dramatically. And that was with RO water and weak (300ppm) nutes and calmag+ about 10 days prior, with plain RO top ups. I'd start the day adjusted to 5.8 and it'd be 5.3 after 12 hours or so.

It's been steadier since the nute change, but I'd sure love to know what could make it drop like that on a daily basis.