Alkalinity perfection

[Acuario]

I've been trying to stabilize alkalinity for the longest time. More recently I went with a larger calcium reactor and a peristaltic pump, and finally an external refugium to add more system volume. Today I was thrilled to see a straight line reading for calcium reactor pH levels for the week! While I've experimented with various settings, what I think finally really stabilized things was to turn the calcium reactor effluent drip way down to 10.2 mL per minute (6 rpm on the Masterflex) with a bubble count of only 2-3 bubbles per minute. If anyone wants more details, just let me know?

 

[blaxsun]

Are we talking about alkalinity or pH?

 

[Acuario]

The Apex graph is displaying the pH level within the calcium reactor. The stable pH for melting the reactor media leads to a very consistent effluent alkalinity measurement which I test manually as well as manually testing alkalinity for the tank itself. It was just kind of fun to finally see a completely flat line for the pH measurement across a week's timespan. In the future, I may go with automatic testing for alkalinity. Anyway, just hoping to be helpful here, sorry I wasn't clear.

 

[J1a]

The rate of consumption of alkalinity changes according to dark/light cycles. Therefore if the goal is to have constant alkalinity, it maybe necessary to micromanage dosing/crx down to per hour basis.

 

[Logical_Plan]

The Apex graph is displaying the pH level within the calcium reactor. The stable pH for melting the reactor media leads to a very consistent effluent alkalinity measurement which I test manually as well as manually testing alkalinity for the tank itself. It was just kind of fun to finally see a completely flat line for the pH measurement across a week's timespan. In the future, I may go with automatic testing for alkalinity. Anyway, just hoping to be helpful here, sorry I wasn't clear.

Great job! Nice to have predictable effluent. Matching tank alkalinity and calcium needs should be easy dosing rate adjustment over time now.

 

[Garf]

Are you sure your probe ain’t shot?

 

[Borat]

Are you sure your probe ain’t shot?

Your PH probe is most likely toast...

 

[Acuario]

Borat and Garf, you’re spot on! Usually the reactor pH varies by .02 or .03 over a week, and corresponds to the rise and fall of the tank pH, so I was amazed it could be so flat. The probe is bad. I tried testing it in a pH recalibration buffer solution and the reading did not move. The probe is 19 months old. You guys are good, thanks for the tip!

 

[X-37B]

I dont even monitor ph or use a controller and my alk stays at +- .3 all the time which is more important than actual ph in the reactor, imo.

 

[gbroadbridge]

The rate of consumption of alkalinity changes according to dark/light cycles. Therefore if the goal is to have constant alkalinity, it maybe necessary to micromanage dosing/crx down to per hour basis.

That's right. I dose hourly during daylight and nothing at night, and normally the variation of Alk is well within the limits and variations of my test method.

 

[Acuario]

Gbroadbridge and J1a, dosing sounds great, especially if you can dial the alk in for the daily cycles and rhythms of the tank like you have. I am invested in my calcium reactor, 2-stage regulator, and peristaltic pump, so I feel like I need to keep going with it. Maybe I'll dose someday too?
90's reefer--good reminder. I test the tank alk most often and effluent alk sometimes to understand their relationship. The reactor pH graph is kind of a bonus, it's always there on the Apex screen. While I thought it was exciting to finally see the graph flat, I learned today it was just a big mistake on my part. Didn't think about the probe being bad.
This hobby is part art and part science. Glad I checked in here. All one can do is keep learning, adjusting, and hope the mistakes don't cost you a lot of coral growth, time and money.

 

[J1a]

I would definitely not consider the day/night fluctuations of alkalinity an issue.

I am dosing the same amount hourly, and have 0.2dkh of day-night fluctuation. So I would expect if you tune your CRx well, the fluctuations shouldn't be too great either.

 

[gbroadbridge]

Gbroadbridge and J1a, dosing sounds great, especially if you can dial the alk in for the daily cycles and rhythms of the tank like you have. I am invested in my calcium reactor, 2-stage regulator, and peristaltic pump, so I feel like I need to keep going with it. Maybe I'll dose someday too?
90's reefer--good reminder. I test the tank alk most often and effluent alk sometimes to understand their relationship. The reactor pH graph is kind of a bonus, it's always there on the Apex screen. While I thought it was exciting to finally see the graph flat, I learned today it was just a big mistake on my part. Didn't think about the probe being bad.
This hobby is part art and part science. Glad I checked in here. All one can do is keep learning, adjusting, and hope the mistakes don't cost you a lot of coral growth, time and money.

Well, I'm dosing a modified Balling 3 Part with Sodium Bicarbonate replaced with Sodium Carbonate, and whatever works for one tank may not work for others.

I have no experience with Calcium Reactors, so can't comment on those.

All I know is that over 3 weeks my tank tested day or night has dropped about 0.2dkh, and that seems perfect to me.

Regards
Graham.