Calcium Reactor and Kalk Reactor

turtleman9100

New member
I will try not to forget anything because I really need you guys help. My system is about 7 month's old now. All my levels are zero. I have a few sps frags some softies and zoos. My aquarium is a 135 gallon with a 40 gallon sump. I have 2 fairly RODI units daisy chained together into one. Here's my problem

I added a CR first. I am using ARM course. My ph inside the CR was 6.5 consistantly. I was dripping about 50-60 DPM with about 30 DPM of CO2. My calcium level dropped to 320 and never increased. While the PH in the tank stayed 8.2, the alk shot up to 22. In the process of this, I bought my KR online strickly for top off. I evaporate about 2-3 gallons per day. I was hoping this would help my calcium level but it never raised. My ALK also stayed in the 20's. I stopped the CO2 in the CR and my ALK is finally dropping. Right now its about 12-13. However, eventhough the KR is still topping off my tank, my calcium appears to still be dropping. I started dosing Kent Marine Tech CB part A only. Still no change in my calcium level. What can I do to get my levels where they need to be? Please help.
 

Randy Holmes-Farley

Reef Chemist
Premium Member
I added a CR first. I am using ARM course. My ph inside the CR was 6.5 consistantly. I was dripping about 50-60 DPM with about 30 DPM of CO2. My calcium level dropped to 320 and never increased. While the PH in the tank stayed 8.2, the alk shot up to 22.

Over what time period? Unless it was very very long, that calcium drop was likely either testing error, or due to changes with a low calcium salt mix. If it is adding enough alkalinity, then it is adding enough calcium (unless you mixed in too much dolomite, a magnesium supplement, into the reactor somehow).

You are not adding anything else, like pH buffers?

If you believe your calcium level is really that low, make a one time correction with calcium chloride (or the Kent calcium part) to 450 ppm, and then the reactor should maintain it (barring water changes with a low calcium mix).

These should help:

Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm

Reef chemicals calculator
http://home.comcast.net/~jdieck1/chem_calc3.html
 

turtleman9100

New member
Thank you Randy for the info. I have 3 different calcium test and I hate all of them. I have really gotten into the routine of water testing. What calcium test do you recommend? I would like to find one easy to use and accurate. As far as water changes, I do 30 gallons every month at once. I am using instant ocean. Is there a better salt, higher in calcium I can use? I am not using ph buffers as the ph in the kalk is high enough to maintain 8.2. Other than the kent, part A (calcium part) I have not dosed anything else.
 

Randy Holmes-Farley

Reef Chemist
Premium Member
I use an older salifert kit for calcium, but I've not carefully compared them in some time. I test quite infrequently (every 6? months). There are plenty of threads in the chemistry forum where folks discuss what kits they like and don't like. :)

IO is low in calcium, so it may need adjustment before use (That's what I do with it). This thread shows values for many other mixes:

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1287118
 

turtleman9100

New member
Randy, Thanks for the info. I made a one time boost with calcium chloride over the last two days. I was able to get my calcium up to 420. As the calcium went up, the Alk came down to 9. My PH was lowered to 7.9 during the day with full lighting. I have since then brought both the calcium reactor and kalk reactor (via topoff) back online. I will continue testing to make sure everything levels out perfectly. Thanks for all of your help.
 
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