Calcium & Magnesium module.

[abhi_123]

Hi,

Can we have expansion modules for calcium & magnesium for monitoring these two important elements of reef tank?

[rimai]

As far as I know, there isn't any probe that can do that.
All ion selective probes I know of can't be used for constant monitoring without rigorous maintenance.
They can certainly be used for causal measurements.

[abhi_123]

Alright.

Any other way to properly maintain the level of ca & mg? Any code which can help or trigger warning when any of these two fall from the desired value.

[rimai]

One solution is to have a servo motor extract the probe from storage solution, flush with RO water, dip the probe into sump, take the measurement, lift the probe again, flush it with RO water nd return it back into storage solution.
That way the probe is not constantly submerged in water.
The only other solution I can think of is an automated colorimeter that would mix reagents and measure the color spectrum, just like hanna colorimeters do.
The problem is that you would have to flush RO to clean after every measurement, prime the lines and still have an extremely accurate dosing device to mix reagents and tank water.
You are probably talking on thousands of dollars for an automated colorimeter and this goes way beyond my realm of knowledge.
I've seen another project that a person did something like this.

[abhi_123]

1000 dollars is not in budget of mine also. I was just thinking of all the possible automation which i can do with the help of my controller.

[ruckusman]

I think it would be cheaper and simpler just to dose larger volumes of fresh saltwater. I would think if you reached a point of dosing slowly enough to turn the volume of the tank a certain amount each month you could in effect based on your population create the same result and just assume you always had basically what the salt is mixed at....

thats my strategy anyways, increase the rate of automatically "dosing" or really changing water. Say 5 gallons a day on 200 total gallons...gets you 150 a month. I would think that would make a good run at anything without a huge sps population. Time will tell.

So that said, I would like to encourage research on dosing pumps that could do this. For now I will just run two small regular pumps for short intervals and see how it goes.

[Sebyte]

I would agree with Ruckusman, regular water changes are the best way to maintain magnesium. As for calcium I top off my tank by running RO/DI water through a Kalkwasser reactor. For me this keeps the Ca and Alk in the range I am looking for.

There are many approaches to maintaining water chemistry, and all of them are neither right or wrong