Calcium Reactor Geekiness

thefu · 10/11/2009, 12:41 PM

So, I wanted to hear from those of you out there running similar Ca reactor set ups to me.

A couple of reef tour visitors commented that my bubble rate might be running to fast. Even though I have it controlled by my Apex and a solenoid.

I figured I had better think things through so I stewed on it in my mind for a couple of hours. I realized that although the bubble rate was not that big of an issue (after all it is electronically controlled), my effluent rate was probably set too high -- therefore not taking maximum advantage of CO2 absorbtion in the media chamber, wasting CO2 and not providing a high enough concentration of Alk/Ca in the effluent per mg of CO2.

Also, if I get the effluent rate set, the optimum bubble rate seems to attainable simply by dialing it back to the point where the CO2 "off" set point is never reached and then just turning it up a bit more. I also contend that setting it to high (fast) will not put too much CO2 into the chamber, but it may make the overshoot at the low (off) set point greater as the effluent change based on CO2 injection has a lag effect. So. with a super fast bubble rate, instead of bottoming out at 6.73 (with a 6.75 set point) you may bottom out at 6.65.

So, after all this mulling around in my mind, I was just wondering what you all run in terms of effluent rate, bubble count, Ph set points, media type and Kh of the effluent itself. I am mostly interested in those running a similar set up to me, that is, modest amount of stony corals and a solenoid controlled regulator on their CO2.

My effluent rate is 15ml/min, my bubble rate is 1/sec, my set points for CO2 control are 6.75 and 6.87, and the effluent Alk is ~36Kh (at that high there is about +/-5% error bound). I have read that the effluent Alk level should be about 3x the desired tank level so it seems OK. For media I use CaribSea crushed media (the finer stuff).

Anyways, I am interested to hear what those in similar set ups are doing.

Michael · 10/11/2009, 02:07 PM

1 bubble every 3 seconds and one drop of water from the reactor every second, the ph is around 6.5 in the chamber, i havent tested the ph in there this week, but its around that figure

LobsterOfJustice · 10/11/2009, 02:58 PM

In my experience...

Choose your pH based on the type of media. Choose your bubble count to maintain that pH. Manipulate effluent drip rate to change amount being dosed to tank.

thefu · 10/11/2009, 03:46 PM

Yes. Set points in my controller are set. bubble count not that relevant when using a controller and solenoid. But the need to adjust your effluent rate to match your tank needs is not linear. It is a bell curve of sorts. If you have it too low the concentration is high in the liquid but not enough goes intothe tank. If the effluent rate is too high then the effluent will have a low concentration and may not bring up the tank no matter how much you add and will in fact just lower your tank ph.

So my point was simply to see where people that use the same media as me have their set points for ph were and what your effluent rate was toaintain proper kh and ca levels given your particular tank demands.

10/11/2009, 12:41 PM	#1
thefu Registered Member Join Date: Nov 2008 Location: SLC, UT Posts: 199	Calcium Reactor Geekiness So, I wanted to hear from those of you out there running similar Ca reactor set ups to me. A couple of reef tour visitors commented that my bubble rate might be running to fast. Even though I have it controlled by my Apex and a solenoid. I figured I had better think things through so I stewed on it in my mind for a couple of hours. I realized that although the bubble rate was not that big of an issue (after all it is electronically controlled), my effluent rate was probably set too high -- therefore not taking maximum advantage of CO2 absorbtion in the media chamber, wasting CO2 and not providing a high enough concentration of Alk/Ca in the effluent per mg of CO2. Also, if I get the effluent rate set, the optimum bubble rate seems to attainable simply by dialing it back to the point where the CO2 "off" set point is never reached and then just turning it up a bit more. I also contend that setting it to high (fast) will not put too much CO2 into the chamber, but it may make the overshoot at the low (off) set point greater as the effluent change based on CO2 injection has a lag effect. So. with a super fast bubble rate, instead of bottoming out at 6.73 (with a 6.75 set point) you may bottom out at 6.65. So, after all this mulling around in my mind, I was just wondering what you all run in terms of effluent rate, bubble count, Ph set points, media type and Kh of the effluent itself. I am mostly interested in those running a similar set up to me, that is, modest amount of stony corals and a solenoid controlled regulator on their CO2. My effluent rate is 15ml/min, my bubble rate is 1/sec, my set points for CO2 control are 6.75 and 6.87, and the effluent Alk is ~36Kh (at that high there is about +/-5% error bound). I have read that the effluent Alk level should be about 3x the desired tank level so it seems OK. For media I use CaribSea crushed media (the finer stuff). Anyways, I am interested to hear what those in similar set ups are doing.

10/11/2009, 02:07 PM	#2
Michael NTTH Rookie Help Join Date: Jan 2008 Location: Gloucester, England,UK Posts: 7,808 Blog Entries: 6	1 bubble every 3 seconds and one drop of water from the reactor every second, the ph is around 6.5 in the chamber, i havent tested the ph in there this week, but its around that figure __________________ Don't be afraid to ask questions, we in the new to the hobby are here to help you [For My Tank Spec,Photo Album,Articles and website, click on my name] MY Very Kindest and Warmest Regards , MIKE Current Tank Info: I have a 92 gal Corner Tank, and way too many pieces of equipment to list really, (proud member of the reef central corner club)

10/11/2009, 02:58 PM	#3
LobsterOfJustice Recovering Detritophobe Join Date: Jan 2004 Location: Cary, NC Posts: 7,443	In my experience... Choose your pH based on the type of media. Choose your bubble count to maintain that pH. Manipulate effluent drip rate to change amount being dosed to tank. __________________ If it's worth doing, it's worth doing right. I remember when zoanthids were called things like "green" and "orange" and not "reverse gorilla nipple." Current Tank Info: 180g reef with all the bells and whistles

10/11/2009, 03:46 PM	#4
thefu Registered Member Join Date: Nov 2008 Location: SLC, UT Posts: 199	Yes. Set points in my controller are set. bubble count not that relevant when using a controller and solenoid. But the need to adjust your effluent rate to match your tank needs is not linear. It is a bell curve of sorts. If you have it too low the concentration is high in the liquid but not enough goes intothe tank. If the effluent rate is too high then the effluent will have a low concentration and may not bring up the tank no matter how much you add and will in fact just lower your tank ph. So my point was simply to see where people that use the same media as me have their set points for ph were and what your effluent rate was toaintain proper kh and ca levels given your particular tank demands.