Mixing Saltwater

[Daddy-o]

I am mixing RODI water with Instant Ocean Reef Crystals Ina 42gal Rubbermaid container. I am noticing a residue at the bottom of the container that is somewhat slimy and tan in color.

What is this? Is is something that should be dissolving in the water? I am heating the water and have a fan circulating it as well.

Should I switch salt brands?

 

[Phranque]

Not an uncommon issue..... google "reef crystals brown residue" and do some reading. I was getting the same thing with Kent Marine as well..... brown crud in the mixing barrel and floating all over the surface. You're seeing the remnants of a clay additive used as an anti-clumping agent. Supposedly there are better additives, but Instant Ocean (and some other brands) continue to use it to keep prices down.... Obviously it's still reef safe, otherwise they wouldn't sell it, but I got tired of adding cloudy water with my pwc's and having to wait a day or two for it to clear up. After I switched to RedSea Coral Pro, I haven't seen it again.... mixing tub is clean & crystal clear water within a couple hours of pwc.

 

[Daddy-o]

Thanks for info!

When switching salt, do I need to slowly start blending the salt in my mixing tub or does the fact that it is a PWC take care of that? I have enough of the stuff stocked up now that slowly switching will not be an issue.

 

[Phranque]

You're supposed to blend salts as you change the tank over, but I just went straight to RSCP and did a bunch of very small back-to-back pwc's to get my tank acclimated.