Calcium Reactor Questions

Last night I was setting up my Cal reactor, and was having issues with the bubbles coming from the C02 tank. My regulator has a bubble counter attached to it, and from there it goes to the reactor which also has a bubble counter attached to it. The issue Im having is that the number of bubbles going through the regulators bubble counter is much more than whats going down the line into the bubble counter on the reactor... I bought some bubble counter liquid from Marine depot and used it on the regulators bubble counter, but didnt have enough for the reactors bubble counter, so it has RO water in it. Could this be part of the problem? The line from the regulator to the reactor is roughly 3 ft long on does a kind of 'S' line down to the reactor. Maybe thats another reason? 

Unless there are unseen bad connections, I don't see a need for two bubble counters. The one located on the CO2 bottle should be enough, right?

The bubble count and effluent rate will be very dependent on your tank's needs. I'd start with 1 bubble per second with the effluent opened all the way. Slowly close the effluent off over the course of a few hours or days to adjust the ph in the reactor (ph of effluent) and maintain it. If you have a ph controller and solenoid this is a lot easier because it will control when to add co2 and your bubble count can be slightly higher than necessary. Once the ph in the reactor is stable, test your tank every day for alkalinity and calcium. Dose to bring the levels to what you want them at and open the effluent slightly if they are dropping or close it if they rise. If you adjust the effluent you may need to adjust the bubble count to maintain a stable ph inside the reactor. Open or close the effluent (and adjust bubble count when necessary) until the alkalinity stays constant throughout a few days.

I'd just ignore the counter with RO water and when the water evaporates, leave it fluid-less.

Each reactor produces at a different rate and each tank needs a different amount of Alk and Ca. At this point it would be hard to predict how long a 5 lb bottle of CO2 will last.

Best procedure I know of is to start by
1) setting the effluent flow to where the drops are connected like a slow stream and
2) setting the CO2 rate at 1 bubble/second.
Then monitor effluent pH to get a baseline. As I recall, effluent pH should be 6.5-6.8 or something like that. I assume you have a controller to monitor pH and control the CO2, though I have used many Ca Reactors without controllers.

I would test Alk and Ca before starting the reactor and then the next day or two to see whether the reactor produced more or whether it produced less than the tank used. Adjust bubble rate acordingly, faster bubbles to dissolve media faster and deliver more carbonate or slower bubbles to deliver less. It might take up to a week to see how it's doing. Alk and Ca should be checked weekly for a while, at least until I felt comfortable with the setup and flow rate and then I would test alk and Ca at least every 4 weeks.

Mark Peterson wrote: Gosh I'm slow.

Where are the probes located? You may try reducing the amount of CO2 going to the reactor. The media dissolves very slowly and you won't be able to watch it dissolve (unless you do what I did and stick 4 large tridacnids in a small tank with a ton of stony corals). Have you tested alkalinity? Calcium?

The effluent should be the same ph as in the reactor. Test alkalinity and calcium of both the tank and the effluent.

No, the effluent water still has a low pH due to the CO2 concentration. CO2 dissolved in water is what a pH reading is all about. Low pH is why the effluent tube must be placed in a remote position of good flow where it can mix with normal pH tank water before reaching any coral. I believe the purpose of the controller is to turn off the CO2 if tank water pH dips below ~8.

I believe that the effluent waters low pH is what originally dissolved the Calcium Carbonate media (CaCO3) and is what keeps the concentrated Calcium and Alkalinity separated in the effluent solution. When the effluent mixes with the passing tank water those molecules are then actively available for use by a body (coral, snail, coralline algae, fish, etc.).

If tank water pH is falling to 7.9 or below, I believe it means there is too much CO2, too fast of a bubble rate. You mentioned slowing the effluent water, but without slowing the CO2 rate, a slower effluent still delivered the same amount of CO2 to the tank, just at a higher concentration in less effluent water. I would suggest trying it again, only this time cut the CO2 bubble rate by 2/3. In other words, if you started at 1 bubble per second, dial it down to 1 bubble every 3 seconds. Also set the effluent flow back to original.

I agree with Ann. What are the Alk and Ca levels before start-up and then after running the Reactor?

Aloha,
Mark



Edited by Mark Peterson - December 16 2013 at 11:36pm

When  I ran my calcium reactor, I also dripped kalkwasser to help off-set the low pH.