What is the safe upper limit of PH

[GAMGAM]

how high is too high. I’m dosing 2L of saturated kalk per night and one tablespoon of soda ash per gallon (dosing 2L of solution a night) and run a recirculating co2 scrubber. I calibrated my probe about a month ago (I’ll do it again tomorrow morning).

alk about 8dkh

overnight PH low is about 8.5

my tank looks fine, my sps are basing well, my fish seem fine, no precipitation anywhere to be seen.

what do I have to watch out for. Is 8.8 or 8.9 or 9 a problem.

my tank was typically running say 8.4-8.6 but I recently picked up a par meter and dialed in my par and bumped up my photoperiod to 6 hours of about 300-350 umol on my bottom glass. I think the recent bump up to almost 8.8 is due to algae growth on the glass.

any thoughts. Everything seems fine and I doubt my probe is off by too much.

 

[Cichlid23]

What are your alk levels at?

 

[GAMGAM]

View attachment 3023500

how high is too high. I’m dosing 2L of saturated kalk per night and about one tablespoon of soda ash per gallon (dosing 2L of water a night) and run a recirculating co2 scrubber. I calibrated my probe about a month ago (I’ll do it again tomorrow morning).

alk about 8dkh

my tank looks fine, my sps are basing well, my fish seem fine, no precipitation anywhere to be seen.

what do I have to watch out for. Is 8.8 or 8.9 or 9 a problem.

my tank was typically running say 8.4-8.6 but I recently picked up a par meter and dialed in my par and bumped up my photoperiod to 6 hours of about 350 par on my bottom glass. I think the recent bump up to almost 8.8 is due to algae growth on the back glass.

any thoughts. Everything seems fine and I doubt my probe is off by too much.

View attachment 3023528

 

[GAMGAM]

8 dkh

7.7 to be more precise

5ml of titrant on a salifert test

 

[Sisterlimonpot]

If youre dosing calcium hydroxide, and if I had to guess... one of the 2 (pH or Alkalinity) isn't correct.

 

[GAMGAM]

They’re both close. Alk is right 100% PH will be high might be able to discount 0.1-0.2 but high. I’ll double check tomorrow.

the recirculating co2 scrubber pushed it way up. Kalk bumped it, the soda ash bumped it up, and the algae bumped it up too.

it’s high

 

[KrisReef]

Mg.
I had a bit of difficulty getting my parameters on target with low Mg. Yours looks ok to start and it changes slowly. Still, I number is not a trend and an error could hide the truth.

I thought pH above 8.5 was a little higher than typical ocean values.

 

[Sisterlimonpot]

When was the last time you calibrated your pH probe. All that dosing and scrubbing on a tank with very little consumption would make me question the accuracy of one of those 2.

 

[GAMGAM]

mg seems stable around 1350

 

[GAMGAM]

About a month ago for the ph cal. It’s close

 

[Sean Clark]

Calibration or testing error. Chemistry does not support the values.

 

[GAMGAM]

It’s gonna be super low C02 that is pushing up the Ph, like I said it was peaking around 8.6 before I bumped up the light which is growing a bit more algae.

don’t spend so much time discounting the results. I’m close. What do we know about high PH

 

[Sean Clark]

@Randy Holmes-Farley
Thoughts?

 

[GAMGAM]

the green algae you see is very new. And the photosynthesis is what is sending my PH to the moon, but it was engineered to be high before.

 

[Sisterlimonpot]

Well I can tell you that I accidentally shot my pH up to 8.60 when servicing my kalk reactor. But I didn't over react and allowed it to go down on its own without any issue. I couldn't tell you the long term effects though

 

[GAMGAM]

I’m not doing anything about it yet. I might buy a PH controller to shut off my skimmer to fine tune my PH to say 8.5.

the recirculating co2 scrubber was the ticket to good PH. And it lasts about 6-8 weeks between change outs (about 2kg per change out)

my sps bases are growing at like 1mm a day. Things are moving. But I do worry about the top.

things are essentially out of control at the moment. But haven’t exceeded a ph of 8.8 yet. And I’d love to understand where the “ditches” are on a reef tank.

 

[Sisterlimonpot]

Why are you also dosing calcium hydroxide?

 

[Sean Clark]

You have been tracking all of these but not pH... and then post about pH?

 

[GAMGAM]

To try to smooth the overnight low.

 

[GAMGAM]

The ph is on a probe. Those are manual tests. Like I said before the light adjustment the overnight low was around 8.4 and high was around 8.6.