Calcium Test help

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Aquarium Advice Apprentice
May 15, 2004
San Diego, CA

I need some help determining a problem testing my Calcium levels.

I am moving up to Shrooms from a FOWLR setup. So now I have a FOWLR + Shrooms tank. :D

I recently purchased a Salifert Calcium Test Kit, and have tried testing my Calcium levels without success twice so far.

The first time was last week. I couldn't get the solution to turn blue, even after using the entire 1ml syringe.

Since I had recently done a water change about 16 hours before the test, I thought that was the problem.

So I waited a week, tried again this morning, and again no luck. The solution stays pinkish-violet. It never turns to clear blue.

Does this mean:

A) The Salifert test is broken (perhaps something was labelled incorrectly or gone bad)?
B) I have TOO MUCH calcium in the tank
C) I have TOO LITTLE calcium in the tank
D) Or something else?

Thanks in advance for the help!
What are your other water parameters (pH, Alk, Mg). Using the entiire sytinge would mean too much Ca, like 590 ppm (don't have the chart handy). Test a sample of freshly made mix and see what you get.

Have you been dosing calc?
How old is the test kit?
Where did you buy it?
Does it have an expiration date on it?

Salifert recently changed the Ca test kit. What are the steps you are performing to test your water sample?
Ok I just did a water change. I use CoraLife salt by the way.

I did the test again using a sample of the freshly-mixed salt, and it finally turned blue. The new batch measured about 450ppm of Calcium (give or take I don't know how much depending on how accurate everything is).

So it looks like the test kit is ok.

I haven't been dosing calc, however I picked up some SeaChem Reef Complete tonight for 5 bucks, just incase I am running low.

I can't imagine I'm running over in Calcium, the tank is about 2 years old and I've never added anything except water changes. It's been a FOWLR tank forever until I decided to move up to mushrooms now.

So I am going to wait 24 hours and do the test again on the main tank water and see what happens.
OK, the chart only goes to 500 when reading 0 on the 1ml syringe.
I would do some 20% water changes till you got the reading down below 500.

I'm curious as to how it got that high if you're not adding anything to the tank.
I would not do anything... Having a Cal level of 500 is not the end of the world, Oceanic salt can be 500 + out of the pail.
You should get a alkalinity test kit also, you need to keep these 2 balanced.. Shroons will be rine with your cal so don't be looking to change anything too fast.
Seaham, He does not know what his Ca level is. Only that is over 500.

Do another test but if you use the full syringe, fill it again and see what it takes to turn blue. Add 500 to this reading and you will know where your tank is now.

You might to look at this article Calcium for Dummies. It helps explain the chemical relationships between Calcium, Magnesium, pH and Alk.
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