Calcium Testing

[TigerIssey]

Hope someone has an answer.

I swapped additives today, was using Seachem Reef Complete but seemed to not last very long at all. Is very good I have to say, 250ml last me a month.

I have bought the TMC equivalent of what are in Reef Complete, ie Calcium, Magnesium and Strontium. I have been testing Ca and Mg all along and as I was going to be adding Sr myself I thought it better to get the test kit.

I am using Salifert test kits. This afternoon, I tested for all three plus alk and pH.

The Salifert Ca gave me 415, lower than I run the system at by quite a bit. I then opened the Strontium and firstly you test for Ca to make sure you are over 300 else the Sr compnent does not work. You then carry on until getting a Ca level before going on to get your Sr level. Here is the problem, on this test my Ca comes out at 452.

This leads nicely to my actual question, which is the more accurate test for Ca, is it the Ca test or the Ca component of the Sr test??

I am reluctant to go by the Ca test as this could lead me to Supersaturating with Ca if the level is actually nearer the Ca component of the Sr test.

Which should I trust.

For extra info Alk = 8.6, Mg = 1290, pH = 8.0. Sr comes out to 0-3.

EDIT - added Sr result

 

[Alex Brown]

Maybe try test with the Ca on its own one more time to see if the results vary? Now its been a day or so, do 2 tests each with each kit, that sould show you if there are any fluctuations. But unfortunately I cannot offer you any advise on what to go by, just getting into the confusing world of adding suppliments myself!

 

[TigerIssey]

I have got an answer off another person elsewhere.

The calcium test is the one to go by.

I have added some Mg to increase my level more to the 1350 mark whereby the Ca level will be easier to adjust and will aid the Ca and Alk stay stable.

Have added some Ca but will recheck all levels tomorrow and add some strontium as that should be nearer 12-16 according to my test kit.

I am only having to add this much in the way of additives to keep my waterchanges to once a fortnight. Being disabled now, it is hard work on me even with andrews help to do more frequent water changes. I keep nitrates and phosphates down nicely by doing once a fortnight but the addition of so many hard corals and even more going in tomorrow night means that I will need to keep closer tabs on the levels and adjust accordingly.

I want to swap to the balling method and use pure chemicals when these run out, problem was it was the middle of the night when I realised how low I was on Reef Complete. Just ordered what I had my head around to start with, although I could have got twice as much in pure chemicals as I did with TMC stuff for the same price.

At least this will let me get my head around dosing more.

Hope that helps you aswell Alex.

 

[SkiFletch]

I hear that TI about the cost of the "branded" additives. I'm still using my 60lb bag of calcium chloride I bought 3 yeaers ago

If I may suggest, try to get away from daily testing (if you are in fact doing this). Try instead to dose a specific amount of calc/alk daily and test again after a week. See if you were dosing too much or too low. At the time of testing, correct for the span of where you are to where you should be (like if calc is 400 and you want it at 430, bump it all up in one shot) using a reef chemistry calculator. Then lets say you were too low on calcium. Increase your daily dose of that, and see where you end up after a week. It'll take you a while to get it right, but you'll eventually really get the hang of your system/s demands this way.

That may be how you're running things already, and if so great, maybe this post will be helpful to someone else looking to stretch out waterchanges.

That reminds me, I need to do one in the near future

 

[TigerIssey]

I am not doing daily testing Ski.

Just trying to get the levels ok in one shot before I go to doing weekly.

This is the first time I am using the powdered addivites so am a little more confused. The Seachem additive kept me stable but the Mag seemed to stick at 1290, am getting this up before adding calcium etc then I will go to once a week.

Hope that makes sense and I do hope this helps others who are starting powdered additive use.