CAl and alk levels

[Farrmanchu]

Mike, why not take the Kalk Reactor off line for a bit, while dripping Baking Soda or other Alk supplement until Ca gets used up. I have the same problem, when I use Kalk alone, Ca rises and Alk drops slowly. The fish and other bioload use up Alk. I find my tank uses around 10ppm a day of Ca, so when I stop Kalk, it drops 10ppm per day, but I keep Alk high with baked Baking Soda dissolved in RO. Once the SPS and Clams get bigger, you may get away with Kalk alone, just more of it, with a bigger demand on Ca from Corals.

[mseepman]

To give you a little more info, my salinity is a 1.023. I have not been dosing anything for quite a while now, although I did up until about 7 months ago using Reef Complete. I have mostly softies, but a few SPS as well. I also have a reasonably decent Bio-load with 10 fish in a 70 Gallon tank. I don't have an RO/DI myself, I purchase RO water from a local vendor (same stuff I drink). I don't use any tap water and have not used any in 2 years. I don't have a lot of new coraline algae growth, but my rocks are nicely purpled up from the last few years.

Any other suggestions?

Originally Posted by untamed

How's your salinity? Maybe you've gotten over-concentrated. You do have an unusual problem, to be sure. You are not dosing anything to supplement Ca/Alk, yet your Ca/Alk is RISING. That suggests that you have nothing in the tank that would use up Ca/Alk. Even a normal growth of coraline aglae would eventually use up Ca/Alk in a tank if there were no supplementation.

Do you happen to have a very clean, fish-only system? I'm baffled by that one.

[untamed]

mseepman, I am at a loss to offer an explanation.

There is no mechanics that I can think of that would allow Ca/Alk to go UP beyond the levels of the replacement SW in any system that is supporting SPS and coraline algae.

I don't think that fish or overall bioload are a factor as they don't pull Ca from the water.

[mseepman]

In order to try and bring things back into line, I am doing a 20% water change this weekend. I did a 20% last week as well but it didn't seem to do much.

Without having my own RO/DI, big water changes are a real pain in the butt!

[Bryan]

I do...have you checked for a faulty test kit. What test kit are you using..A lot of problems with Salifert as of late, could be your alk or Ca test kit.

Originally Posted by untamed

There is no mechanics that I can think of that would allow Ca/Alk to go UP beyond the levels of the replacement SW in any system that is supporting SPS and coraline algae.

[mseepman]

I thought the same thing...but I have a Hagan test kit and the Salifert and both read similar. I bought the Salifert kit after getting these readings from the Hagen kit. I have a friend with a red sea kit (ugly I know) but I will have him do a test and see if he confirms.

[Captainhemo]

Test the RO water you are buying for Ca, not being run through a DI filter I'd bet it contains Ca.
As mentioned by Scumchug, you are then adding Ca everytime you top up your tank and slowly increasing Ca levels.

[mseepman]

I will try testing it, but wouldn't it show when I test my newly mixed salt water too?