Red Sea Calcium powder supplement

abinder · Jan 19, 2016

I recently picked up some Red Sea Calcium powder supplement.

When I mix it up at the recommended dosage (550g powder to 1 liter of RO) I get some residue that doesn't fully disolve into the RO water that I'm using. I'm even heating up the RO water on the stove to help it mix.

Has anyone else experienced this?

Thanks for any info or advice.

Allen

Randy Holmes-Farley · Jan 20, 2016

How much material are we talking about? Just a fine dust? Is it colored?

Was the container definitely clean before use, with no chance of any alkalinity supplement residue in it?

Some sources of calcium chloride have some residue in them. Sometimes it is brownish, and may be an iron impurity. While I've not heard about it for this brand in particular, I wouldn't worry about it if it is a small amount.

abinder · Jan 20, 2016

It did appear to be a fine 'dust' that had a brownish color to it.

The container was definitely clean before use and was rinsed with RO before mixing it.

I ended up pouring it through a coffee filter (the type used in drip coffee makers). I took a long time to 'strain' it though. Hopefully, the only things that were strained out was the 'fine dust' residue and the liquid that went through was full strength calcium supplement.

Thanks for you input.

Allen

biom · Jan 21, 2016

I experienced the same brown-orange residue when used Red Sea Calcium Chloride few years ago. This was the reason to switch to another supplier. This is an impurity and to be honest even high purity CaCl2 tend to form whitish residue after dissolution (formed from CaCO3, CaSO4 and in some cases Ca(OH)2) but in RS powder the problem is the brown-orange color of residue, which is signal of presence of metallic ion or organic compound. May be it is harmless or even intended, but me personally I don't like the idea to put that crud in my tank.
I'm doing this simple test every time I'm switching from calcium products - after dissolution, I'm leaving to rest overnight and looking at residue color - if it is pure withe without blue or brown or orange tint, then it is OK.

abinder · Jan 21, 2016

What brand supplements are you using ?

biom · Jan 21, 2016

No brand, because of my work I have access to lab grade reagents. But I know you have in US reef staff suppliers like BRS that offer good grade supplements.