Two calcium reactor questions

[comatose]

At what PH in the calcium reactor does the calcium reactor media stop dissolving and not produce anymore Alk?

and at what point(PH) does the media start turning into MUD?

I don't want anyone telling me what they heard on here what it should be, I want facts, has anyone ever did the testing and know for sure on both questions above?

For the sake of argument lets say weââ"šÂ¬Ã¢"žÂ¢re using A.R.M.

 

[Randy Holmes-Farley]

At what PH in the calcium reactor does the calcium reactor media stop dissolving and not produce anymore Alk?

The answer to both depends on the media (some are aragonite,some are calcite, and particle size/surface area will also be important), and how long you wait. As soon as the pH drops below the mid 7's, some can dissolve, but it is not rapid until it drops down into the 6's, typically. At a pH not to far below where it is dissolving rapidly, it dissolves too rapidly and forms what folks call mud. I do not know specific values for ARM media, but perhaps others can chime in.

Personally, I do not think the pH in the reactor is the goal, and I wouldn't even bother to measure it unless I had some sort of unusual problem. I'd gauge the reactor by the alkalinity of the effluent and the tank.


You might find these useful:

A Guide to Using Calcium Reactors
http://reefkeeping.com/issues/2002-05/sh/feature/index.htm

Calcium Reactor setup calculator (CaCO3/CO2 reactors)
http://home.comcast.net/~jdieck1/reactor.html

 

[comatose]

well i kinda figured there wouldn't be any one answer because of all the media types out there, which is why i gave my media type in my first post.
I built a CR last year it works great and keeps the tank stable, just not under pressure because of a few leaks that developed around the lid seals, so i had to put the needle valve before the tank water enters the CR and adjust the drip that way.
anyway i'm in the process if making a new reactor(duel chamber) and want a PH probe in the main reactor chamber with a compression fitting.
I decided on the probe in the main chamber because I see people with duel chamber reactors measuring the PH of the effluent into a cup and adjusting the PH that way, and if they set that at 6.5 then the main chamber is probably much lower which could produce MUD.
I was more or less just curious with my questions in my first post to satisfy my own curiosity.
When I finish this new reactor I am curious what the difference in PH is from the main chamber and the effluent dripping into the tank is, mainly because I want to see how effective the second chamber really helps on raising the PH before entering the tank. I know it also depends on the drip rate since a higher drip rate will have less contact time with the media in the second chamber.
But Iââ"šÂ¬Ã¢"žÂ¢ll find out soon since Iââ"šÂ¬Ã¢"žÂ¢m almost fished the new CR, the main chamber probe will be connected to a PH controller so Iââ"šÂ¬Ã¢"žÂ¢m not really worried about a mud event

 

[Randy Holmes-Farley]

I decided on the probe in the main chamber because I see people with duel chamber reactors measuring the PH of the effluent into a cup and adjusting the PH that way, and if they set that at 6.5 then the main chamber is probably much lower which could produce MUD.

Yes, one would not want the pH in the second chamber or the effluent to be that low in such a case.

When I finish this new reactor I am curious what the difference in PH is from the main chamber and the effluent dripping into the tank is, mainly because I want to see how effective the second chamber really helps on raising the PH before entering the tank.

It certainly can raise it, but it will be interesting to see by how much. Same for the overall tank pH.