Purple Up actually not junk

[Randy Holmes-Farley]

That's the missing piece of information. If that information was mentioned in your article, then I must have missed it.

My article was written in early 2002, long before Caribsea sold Purple Up, or at least before we heard about it here. Their only product containing that 10 micron aragonite of theirs at the time was Aragamight and a slurry version, Aragamilk. Now they say Purple Up contains it as well, on their web site linked above.

 

[Ãœbermensch]

thanks.

 

[Randy Holmes-Farley]

:thumbsup:

Happy Reefing.

 

[fwbfirearms]

I read you article about Calcium monitors. That is a great point about when doing the titration, the pH changes so that the aragonite can further dissolve and change the calcium reading. A probe does look like the way I may go. What if you were to run a sample of seawater through a 1 micron or less filter? Any idea of what degree this might improve a calcium test reading? Or are we still far some the scale we desire?

 

[FLSharkvictim]

Randy is this Purple up affect your inverts in any way?

 

[bertoni]

Randy isn't posting here very often anymore. Purple Up is basically just fine sand plus a bit of calcium chloride and some trace elements. It should be safe with invertebrates.

 

[blasterman789]

Yeah...'Purple up' isn't junk....just kind of irrelevant. It's basically just aragonite sand and some other ingredients....I also hear it has iodine it. Grind up some of your crushed coral substrate and that's what it is.

Aragonite / calcite is just a 'fat' molecule of calcium carbonate, and calcium carbonate should be saturated in a salt water tanks anyways.

The reason purple up kinda works in some instances is smaller tanks can have a problem keeping natural calcium carbonate levels saturated, and coraline algae is really sensitive to calcium carbonate levels. That's why tanks that use reactors or really 'thick' well water tend to grow massive amounts of coraline.

I use straight calcium carbonate powder in my smaller tanks. Larger tanks should have sufficient mass of LR or substrate to keep calcium carbonate levels naturally saturated this helps keep dKH stable as well.

 

[bertoni]

As you mentioned, calcium carbonate is supersaturated in saltwater, so neither Purple nor aragonite will dissolve in saltwater. The mass of live rock in a tank is irrelevant until the pH drops to very low levels, 7.2 or lower, or maybe if the alkalinity is dropped to very low level with an acid. Calcium carbonate powder won't work, for the same reasons.