Tan residue - salt mix can

[MJV0103]

Okay, so I had an old heater and two power heads in my 20g brute can. It held about 15 gallons of salt water in it for a week or so. When I popped the top their was this tan residue over everything, one of the pumps wasn't working and it looked like the heater had malfunctioned. Tossed the water, pump, and heater, cleaned out the can and the working pump really well, did another batch, it's back. Any idea what this could be?

 

[Rybren]

It's mostly calcium carbonate with a bit of magnesium mixed in. Nothing to worry about. My SW container hasn't been cleaned in at least 5 years. You should see the build-up in there.

http://www.reefkeeping.com/issues/2005-07/rhf/#2

 

[hkgar]

I have the same issue and store my mixed salt water in a 32 G Brute and it is for my AWC. I had previously posted about it and someone suggested an voltage leak from my Maxijet that I used for water circulation. I removed the pump and problem didn't stop, so I like this idea of precipitate of calcium carbonate.

 

[theatrus]

What salt are you using? I've noticed this primarily with reef crystals, a lot less to non-existent with hW Reefer.

 

[hkgar]

I's using Red Sea. (not the coral plus)

 

[BarryV]

I am getting the tan residue the last few time I mixed my the
saltwater. I have been using the same salt mix for a couple of
years (kent marine reef salt mix). I am thinking it might be the
temperature of the water. I only seem to have the problem in the warm summer months.
Barry

 

[MJV0103]

Reef Crystals. And it's good to know this. This time last year I was only using reg instant ocean and was mixing 3G at a time in a container and doing the hand shake and mix dance

 

[Taahirs]

Also have a lot of the stuff. Haven't cleaned the drum in a good few years. Using seachem reefsalt or Aquavitro salinity.