Riding the stressful PH high (Actually, High PH... :) )

[WhatCouldGoWrong71]

Thanks in advance if you are taking the time to respond to this, I think I have covid, so I hope I am making sense:

I am trying different methods in my two displays. First:

Both tanks have new PH probes connected to my Apex (2 weeks) and have been calibrated twice in 10 days. I have also double checked the readings with a Milwaukee 122, that I also have calibrated twice, the probe on this is about 8 months old.

First tank is a Reefer 250 (bedroom reef). I am running kalk opposite light schedule, about 2Gs which is about 85% my evap. I have soda ash in for my alk. I had sodium hydroxide in but I pulled it out of fear for now. I also am recirculating a CO2 scrubber. In this tank I have about 30-36 SPS (acro) frags.
DKH - 8.21
Cal - 435
MG - 1409
PO4 - .09
NO3 - 22.00 (working on it)
Tank has 70 pounds of wet gulf premium rock in it.

I am having a hard time keeping up with the alkalinity and calcium uptake. To put it in perspective 2 weeks ago I was dosing about 40ML and today I will put in over 300MLs, that does NOT include what the kalk equates to. My PH easily lives above 8.5. In fact I pulled the sodium hydroxide when I hit 8.65 out of fear and put a little vinegar in it, more for my nerves I guess, lol. I set a rule for the outlet overnight to shut the Versa down >8.51. But during the day, if I shut the DOS down (which is doing the 2 part) my DKH plummets. I'd like to set up Sodium Bicarb and Sodium Hydroxide with the identical dosing schedules. But add a rule where the bicarb only doses >8.55 PH and the Hydroxide doses below 8.55. I think I will be able to take the recirculator offline by doing this, and just scrub for CO2. Is there any downside to me doing this? I am simply blown away by the exponential uptake.

My second tank is a Max S500 (Red_Sea_S500), >4 years old.
DKH - 8.37
Cal - 487
MG - 1501
PO4 - .06
NO3 - 11.50 (working on it)

CO2 Scrubbing no recirculator, Dosing Sodium Hydroxide as part of my 2-part, using kalk opposite light schedule, about 2G which is 60% my evap and it is a mixed reef. I am a couple days into raising my PH in a meaningful way and I am not seeing any real need for a increase of dosing to compensate for a massive spike in uptake like my other tank. Which is odd to me. But, I am just a guy who is likely about to blow his crap up.

So my second and equally important question is, what PH value should I shut everything down at, what is the ceiling to put a safety valve in?

 

[WhatCouldGoWrong71]

Well, let me walk back the comment about the uptake on the Max. I thought my testing was set to more often than I had it. In a period where I dosed 100ML, my DKH dropped .67. I also had my Trident set to increase 50%, and obviously didn’t keep up.

 

[Randy Holmes-Farley]

I'd like to set up Sodium Bicarb and Sodium Hydroxide with the identical dosing schedules. But add a rule where the bicarb only doses >8.55 PH and the Hydroxide doses below 8.55. I think I will be able to take the recirculator offline by doing this, and just scrub for CO2. Is there any downside to me doing this? I am simply blown away by the exponential uptake.



So my second and equally important question is, what PH value should I shut everything down at, what is the ceiling to put a safety valve in?

The first point sounds like a fine plan, but I'm not sure just turning off the recirc will keep the pH from getting above your target.

I think anything above pH 8.6 should be considered experimental. The main risk I know of is accelerated precipitation of CaCO2 on sand, heaters, pumps, etc.

 

[merkmerk73]

The first point sounds like a fine plan, but I'm not sure just turning off the recirc will keep the pH from getting above your target.

I think anything above pH 8.6 should be considered experimental. The main risk I know of is accelerated precipitation of CaCO2 on sand, heaters, pumps, etc.

Randy - would you not worry then at 8.57 PH?

I've been using a recirculator and even with a Y valve being completely open, it's been enough to keep my PH very high after recent calibrations.

 

[Randy Holmes-Farley]

Randy - would you not worry then at 8.57 PH?

I've been using a recirculator and even with a Y valve being completely open, it's been enough to keep my PH very high after recent calibrations.

If you do have have excessive precipitation problems, I would not worry.