pH impact on Alkalinity and Calcium?

[Eichen]

Hello,

I have thriving 220g sps tank. Two months ago I installed pH probe and started monitoring the swings during day and night. My pH values on that time were between 7.9 at night and 8.1 at day. That time I dosed 165 ml of balling solutions of each container.

I decided to increase the pH with co2 scrubber to see how my corals would react. The impact on pH was fast and now my pH is 8.3 night and evening before lights go out it´s 8.47. Corals have responded very well with better polyp extension and growth speed. I knew my dosing consumption would go up to maintain KH in 8.5 and CA in 430 values. But I did not expect that I would need to dose 320 ml of each container during 24h to keep them in level.

My question is: Would it be easier (lower dosing quantities) to keep my KH and Ca in level with pH around 8.45 if I would settle for lower KH and Ca values?

I assume that I increased the abiotic precipitation and consumption by corals by increasing pH. But would be nice to keep the pH in this range with slightly lower balling solution consumption.

M

 

[chipmunkofdoom2]

I assume that I increased the abiotic precipitation and consumption by corals by increasing pH. But would be nice to keep the pH in this range with slightly lower balling solution consumption.

Increased pH generally increases the rate of calcification. More calcification requires more carbonate alkalinity and calcium. If you don't want to dose more two-part, why not remove the CO2 scrubber and let the pH (and thus, calcification) decrease? Plenty of amazing tanks have been kept with a pH between 7.9 and 8.1.

 

[chipmunkofdoom2]

Also, welcome to R2R @Eichen! Feel free to introduce yourself in our Meet and Greet forum, as well as posting a tank thread in our Member Tanks forum

 

[Eichen]

Thank you chipmunkfdoom2. I did this just to test how the increased pH affects my tank and I was positively surprised how corals responded. I will have to figure out will I continue or just let the pH run its own course. In any case I have now 8L balling containers so I would not run dry of dosing too quickly

I will have to do the meet & greet + tank forum

 

[chipmunkofdoom2]

Thank you chipmunkfdoom2. I did this just to test how the increased pH affects my tank and I was positively surprised how corals responded. I will have to figure out will I continue or just let the pH run its own course. In any case I have now 8L balling containers so I would not run dry of dosing too quickly

I will have to do the meet & greet + tank forum

This sounds like a good plan. I was just curious why you wanted to have higher pH. Most people try to increase pH because it makes corals grow faster. If your tank is using too much two-part, you could dose less and lower the calcium and alkalinity levels. But, this will cause the corals to grow more slowly. If the corals are growing at a slower rate because the calcium and carbonate alkalinity is lower, I personally would not attempt to control the pH too tightly.

If I was in your situation, I think I would give the corals as much two-part as they could use and run the higher pH. Higher pH definitely has benefits in reef aquaria. But, I'm fortunate enough to have lots of cheap two-parts available in the US. Retailers like Bulk Reef Supply sell 4 liters of calcium and carbonate alkalinity solution for as little as $14 USD (about 12 EUR). Two part could end up being a significant cost, depending on what you have available.

 

[Scorpius]

Your Ph was perfectly fine before the addition of the C02 scrubber. No reason to run one for your system.