Bubble rate in calcium reactor?

[Ocelaris]

Hello, first time calcium reactor owner. I've read jda's calcium reactor tuning guide and I get the principles, but I'm worried I'm using too much co2? I have a korallin C1502 with a co2 art Regulator and stp peristaltic pump. I'm getting 26dkh effluent with small reborn (all I could find) with a pH at 6.67. I'm not using the solenoid to maintain the pH, but I'm doing almost 2 bubbles per second at 30ml/minute, so I'm worried the co2 is going out the effluent. My pH in the tank is pretty high though with a kalk reactor and airline outside to the skimmer hitting 8.5, and dkh in the tank is steady today (first full day on the reactor) at 8.6.

Should I be worried about the co2 use or is that reasonable? Thanks

 

[Shirak]

26dkh on the effluent and pH 6.67 in the reactor seems reasonable and don't think you are putting CO2 directly into the tank. Keep an eye on tank dkh and tweak the reactor as needed to keep the tank where you want it. Slow the bubble count if your alk is climbing and increase if dropping. You could go down around 6.5 pH on reactor if needed. After that point, if you still need more CO2 increase effluent flow so you don't turn the reborn to mush by going too low on the reactor pH.

 

[Ocelaris]

Thanks, I had a bit of air/co2 in the top of the reactor, so I purged it, not sure if that's normal for this reverse flow reactor, but I'll keep an eye on it.

 

[AcanthurusRex]

Very similar to my values. Doing the same thing but with a geo.

 

[Shirak]

Thanks, I had a bit of air/co2 in the top of the reactor, so I purged it, not sure if that's normal for this reverse flow reactor, but I'll keep an eye on it.

I have a small Geo so not familiar with the one you are using. They do take a day or two for all the trapped gases to work their way out. If you see more gas accumulating under the lid over time then you might need to look into it further. It may be a nonissue too if effluent flow, reactor pH, tank alk are all staying stable over time.

 

[Shirak]

I took a quick look on a vendor site and it looks similar to Geo in function with the pump intake at the top and water circulating from bottom to top. Sometimes with these you get a little gas under the lid. It kind of depends where the effluent exit is and whether it is removing it. Most likely it is air from the media on startup. Depending on your sump and where you are pulling water to the reactor it could also be some micro bubbles getting in that way.

 

[Ocelaris]

Thanks, this is my first calcium reactor, but I've been in the hobby off and on for decades, so it's just a function of getting the hardware to work properly. I replaced the original airline compression fittings that were worn, and had to drill out the a fitting to make the CO2 bubble counter piece fit; so the bubble counter in the reactor seems to be bypassed (bubble counter on the regulator works fine). I'll keep an eye on the gas level in the top of the chamber over time to see if indeed I'm accumulating excess.

Am I wrong to assume you can get to stable alkalinity in the tank a number of ways? i.e. from 10 dkh effluent @ 100ml/m to 100 dkh effluent @ 10ml/m just as an example of ranges? Not that those numbers are real, but stoichiometrically speaking they would end up being the same, with just different internal pH values in the reactor and flow rate... Reading JDA's tuning guide (https://docs.google.com/document/d/1VVDp1UOhxK1by9ofK0K83q2RyArEAEYtueOuUFy4SzI/edit) , and assuming there is wiggle room in the 20-30dkh range, it would lead me to believe there is some flexibility... Thanks

 

[Shirak]

Thanks, this is my first calcium reactor, but I've been in the hobby off and on for decades, so it's just a function of getting the hardware to work properly. I replaced the original airline compression fittings that were worn, and had to drill out the a fitting to make the CO2 bubble counter piece fit; so the bubble counter in the reactor seems to be bypassed (bubble counter on the regulator works fine). I'll keep an eye on the gas level in the top of the chamber over time to see if indeed I'm accumulating excess.

Am I wrong to assume you can get to stable alkalinity in the tank a number of ways? i.e. from 10 dkh effluent @ 100ml/m to 100 dkh effluent @ 10ml/m just as an example of ranges? Not that those numbers are real, but stoichiometrically speaking they would end up being the same, with just different internal pH values in the reactor and flow rate... Reading JDA's tuning guide (https://docs.google.com/document/d/1VVDp1UOhxK1by9ofK0K83q2RyArEAEYtueOuUFy4SzI/edit) , and assuming there is wiggle room in the 20-30dkh range, it would lead me to believe there is some flexibility... Thanks

Correct you can get the same stability with different flow rates and reactor pH, ie lower flow lower pH or higher flow higher pH, to a point.. Too high a flow and pH and the media doesn't dissolve as well and too low and it will just melt to mush. I think it was Randy Holmes-Farley who said the amount of carbonate added to the tank depends on the amount of CO2 added whether it was at a low pH in the reactor and low flow or higher pH with higher flow it didn't matter. However once you start hitting 6.5 pH range it's time to increase effluent flow so that you can increase the CO2 futher. Which can be done with faster bubbles or bigger bubbles! SO there is some amount of flexibility and tweaking there too. It may take a day or two or three for changes to become fully apparent.