View Full Version : Calcium reactors?
kookerson
02/08/2007, 05:59 PM
After doing all my research (almost a year now!), and just reading that new thread on the cheap DIY Calc. reactor (VERY nice BTW!) in the DIY Forum, there is still on aspect of Reef Keeping that boggles my mind......calcium reactors! Is there a "Dummies FAQ" for these things or is everyone just learning by trial? How do they work? How does it keep your Calc. levels in check and make sure that its not pumping in too much calcium? How, how, how......... any help would be greatly apprecited and would ease my mind!
MCary
02/08/2007, 06:16 PM
Okay, simple...
Coral is made up of calcium carbonate. In order for Corals to maintain their calcium skeletons the water must have a pH of ~8 or higher. Once pH drops to a certain level, the calcium carbonate that makes up the coral skeleton dissolves back into solution. Since this is calcium from a coral skeleton, it only makes sense that it is great calcium for a coral skeleton.
Now the reactor. The safest and most effecient way to lower the pH in saltwater is to mix it with CO2. But if you just ran a bubbler in your tank with CO2 the tanks pH would drop, bad, but not enough, bad, and the CO2 would mostly just gas off into the atmosphere. So the reactor is filled with crushed coral (reactor media) and seawater is circulated through the media as CO2 is injected into it. This lowers the pH and dissolves the coral. The resultant liquid is very high in calcium and has a very high kH. This water is then put into the tank and Viola Bob's your Uncle, you have a low maintenance calcium dosing machine.
So, where to set the maching. The instructions usually give you a good starting point. You want a pH of around 6.5 and a dKh of, if I remember, around 60. A lower pH will dissolve your media too fast. In order to maintain those levels, you either have to adjust your CO2 or your flow through rate. Fast flow, more being added to tank, more CO2 is needed to maintain pH. Opposite give opposite results.
The way you determine how much is to determine your tanks needs. Suppose you want to keep your tank at 400 ppm Calcium. First you adjust to 400 ppm with a calcium supplement. Then you measure the next day your calcium level. If it drops, you open up the reactor a little or increase your bubble rate, if it goes up, you back it off.
Easy breezy lemon squeezie.
Mike
kookerson
02/08/2007, 06:29 PM
Sounds pretty clarified now! So, basically, your Co2 is what controls how much of the media gets disolved, which, in turn, is how much Calc. gets released into the system, right? Oh and where does dKh come in? thats your Alk, right?
kookerson
02/08/2007, 07:37 PM
So let me pose one more question. It seems like in a Calcium Reactor System, there are a few things that could get outa wack. Do people generally prefer to have these Calc. Reactor systems, or do you prefer the daily task of supplementing their calcium by hand (such as with Doc Randy's 2-Part)?
vBulletin® v3.8.4, Copyright ©2000-2024, Jelsoft Enterprises Ltd.