pH, 2 part and Kalk dosing question.

USMA36 · Sep 10, 2020

Randy Holmes-Farley said:
Excess CO2 in your home air is almost certainly the explanation. The only other possible explanations are excessively low alkalinity, or very poor aeration with your home air.

This has more:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

I am hoping that my low ph was caused by putting my maxspect gyre together backwards. They work poorly when the paddles are on backwards. Forgive me for not grasping this but Is there an equation to figure out the math for cutting my esv 2 part by half and adding a specific amount of kalk per day to help raise the ph? I have 5 people in my house and I live in the northeast. I already have the skimmer drawing fresh air from the outside.

nereefpat · Sep 10, 2020

USMA36 said:
Lol. Thank you. I'd like to cut my 2 part dosing and suplament with kalk to raise my pH. Is it possible to do that through the my ato? I can't wrap my head around the math.

People do use kalk in ATOs, but I don't necessarily recommend that. It's better to use a doser, or even a dripper, or a pump on a timer. Kalk in an ATO isn't an exact science, since evaporation fluctuates a bit, and you may not want to use fully saturated kalk in an ATO because it's hard on equipment.

You'll have to play around with it a bit and see if you like the results. Try cutting your 2 part in half and do the other half with kalk. Test frequently.

USMA36 said:
Forgive me for not grasping this but Is there an equation to figure out the math for cutting my esv 2 part by half and adding a specific amount of kalk per day to help raise the ph?

The math is in the calculator, as far as figuring out how much of each to add and what the effect on alk will be. The math for how much pH will change would be exceedingly difficult to determine. Now, if you dumped a known amount of saturated kalk in a known volume, the anticipated effect could be calculated. But, since kalk is dosed throughout the day and the tank is constantly exchanging CO2 with your house, it isn't cut and dried.

USMA36 · Sep 10, 2020

How long should it take for the Co2 level to drop and the ph to rise back above 8 given good surface agitation andy house opened up?

USMA36 · Sep 10, 2020

nereefpat said:
People do use kalk in ATOs, but I don't necessarily recommend that. It's better to use a doser, or even a dripper, or a pump on a timer. Kalk in an ATO isn't an exact science, since evaporation fluctuates a bit, and you may not want to use fully saturated kalk in an ATO because it's hard on equipment.

You'll have to play around with it a bit and see if you like the results. Try cutting your 2 part in half and do the other half with kalk. Test frequently.

The math is in the calculator, as far as figuring out how much of each to add and what the effect on alk will be. The math for how much pH will change would be exceedingly difficult to determine. Now, if you dumped a known amount of saturated kalk in a known volume, the anticipated effect could be calculated. But, since kalk is dosed throughout the day and the tank is constantly exchanging CO2 with your house, it isn't cut and dried.

Thanks for taking the time to try and explain it. Before I try and figure out the kalk to 2 part ratio I will give it another day to see if agitating the surface more helped. I started this morning at 7.61. Lights maxed at 1130 and stay that way until 730. Ph is now 7.83 so it is creeping up little by little. I guess I was hoping it would be faster.

Randy Holmes-Farley · Sep 10, 2020

USMA36 said:
Lol. Thank you. I'd like to cut my 2 part dosing and suplament with kalk to raise my pH. Is it possible to do that through the my ato? I can't wrap my head around the math.

Yes, I did it that way for 20 years (no two part use), but it can lead to somewhat more variability in dosing based on evaporation, and hence more variability in alk (if that concerns you).

Randy Holmes-Farley · Sep 10, 2020

USMA36 said:
How long should it take for the Co2 level to drop and the ph to rise back above 8 given good surface agitation andy house opened up?

The more aeration with high Co2 air you have, the faster the pH will drop after adding kalkwasser.

The rise effect of kalkwasser on pH is instantaneous.

USMA36 · Sep 10, 2020

My pH is back down in the 7.65 range tonight. House has been opened up all day. Highest I got was 7.85. I don't get it. If it was Co2 the house has been opened all day and the tank surface has been roiling all day . Window near tank and screen door directly across were both open. I would think Co2 would have vented. Surface agitated very well. With 2 maxspect gyres on random at 100% and an mp40 on the back wall at 30%.

USMA36 · Sep 11, 2020

Dropped to 7.5 overnight. I'm worried that prolonged at these low levels will mess up my coral.

Randy Holmes-Farley · Sep 11, 2020

Try my aeration test in this article:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

The Aeration Test

Some of the possible causes of low pH listed above require an effort to diagnose. Problems 3 and 4 are quite common, and here is a way to distinguish them. Remove a cup of tank water and measure its pH. Then aerate it for an hour with an airstone using outside air. Its pH should rise if it is unusually low for the measured alkalinity (Figure 2). Then repeat the same experiment on a new cup of water using inside air. If its pH also rises, then the aquarium’s pH will rise simply with more aeration because it is only the aquarium that contains excess carbon dioxide. If the pH does not rise in the cup (or rises very little) when aerating with indoor air, then that air likely contains excess CO2, and more aeration with that same air will not solve the low pH problem (although aeration with fresher air should). Be careful implementing this test if the outside aeration test results in a large temperature change (more than 5°C or 10°F), because such changes alone impact pH measurements.

USMA36 · Sep 11, 2020

Randy Holmes-Farley said:
Try my aeration test in this article:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

The Aeration Test

Some of the possible causes of low pH listed above require an effort to diagnose. Problems 3 and 4 are quite common, and here is a way to distinguish them. Remove a cup of tank water and measure its pH. Then aerate it for an hour with an airstone using outside air. Its pH should rise if it is unusually low for the measured alkalinity (Figure 2). Then repeat the same experiment on a new cup of water using inside air. If its pH also rises, then the aquarium’s pH will rise simply with more aeration because it is only the aquarium that contains excess carbon dioxide. If the pH does not rise in the cup (or rises very little) when aerating with indoor air, then that air likely contains excess CO2, and more aeration with that same air will not solve the low pH problem (although aeration with fresher air should). Be careful implementing this test if the outside aeration test results in a large temperature change (more than 5°C or 10°F), because such changes alone impact pH measurements.

I ordered an airstone I'll try that on Monday. I have a big fan blowing over my tank drawing outside air in. PH has been slowly increasing all day. It's up to 8 now. Taking a lot longer than I thought it would. I don't know why all of the sudden the ph is an issue. The tank is 3 years old. Nothing has changed in the house.

USMA36 · Sep 12, 2020

Tank only made it to 9.95 today. I still have a fan blowing fresh air from a window over the tank and 2 gyres at the surface making good sized waves. We left the house opened up all day with nobody home for 11 hours. I would have thought that would have really helped but no luck. This is really driving me crazy. ive calibrated then new pH probe 3 times now Thinking it maybe was an apex or a probe issue.