How fast is to fast rasing pH?

[sa52]

Hey guys have been dealing with low pH since I setup my tank and yesterday decided to do that aeration test and it confirmed what I thought of high CO2 in my house. My pH has ranged from 7.7 to 8.0 from lights on to lights off. This morning I ran a hose from the skimmer intake to outside and my pH has gradually risen from 7.69 (9 AM) to as of right now 8.03 (2PM). My question is this change dangerous to my tank? I am not sure how I could make it more gradual. Thanks.

 

[Randy Holmes-Farley Verified Community Expert]

There's no concern about how fast pH changes within the "normal" ranges for a reef tank.

 

[redfishbluefish]

Many see that range of pH swing daily for lights off to lights on....as you have also pointed out....without issue to their tanks. My question is that you've stated that you have this 3/10 of a pH swing every day, and now you're saying running air from the outside "fixed" the pH swing problem. How do you know the upswing you've seen today is from fresh air and not from "lights on?" It's the same swing you've been seeing every day. The question of fresh air will be answered tonight when lights go out....and see if the pH stays up around 8.

 

[Marc.The.Shark]

yeah, normal range is 7.8-8.6. I shoot for 8.3 or so, but don't chase it, you'll drive yourself nuts. Especially with a newer setup, It'll stabilize when your tank matures a little more ~ 6month mark. Mine swings from 8.1 at night to sometimes 8.4 during the day (lights on). And I also run reverse lighting on my fuge

 

[sa52]

Thanks Randy thats good to know.

Red - My worry was not the 3/10 of pH swing a day, it was more of raising my baseline pH because I am now using fresh air from outside. So this morning lights out my reading was 7.69. My lights are still out because my light period starts at 4 in the afternoon. The pH for that last hour or so has stabilized around 8.03 to 8.05. Where my worry came from is now I believe this ~8.05 is my base pH and when lights go on the pH will raise even more as it normally. So I basically could see a change from 7.69 this morning (No outdoor skimmer line/ Lights off) to 8.2-8.3 later today (Outdoor skimmer line / lights on). It was that .6 potential change in a day that had me worried.

 

[redfishbluefish]

Got it @sa52......thanks for the explanation. Still feel you have no problem with that big a swing. Glad to see you've got the problem solved. Let us know what you find when the lights come on.