Caribsea purpleup......

[STHILL]

So does anyone know if the caribsea purpleup works???

 

[ReeferGirl]

I used it a couple times, but you have to keep a close eye on your calcium levels. all it does it raise it up, regular water changes will make the coraline spread. I do weekly WCs and the coraline is really spreading in my tank.

 

[batt600]

Reefergirl is right and it aslo raises mag as well . If you have a rock with coraline on it just take a power head and have it blowing on the rock that will spread the coraline you can scrap it off the rock that will spread it also.

 

[Boomer]

So does anyone know if the caribsea purpleup works???

It does about nothing as aragonite can not dissolve in seawater at normal pH. Too often is the case that the fine power of PU remains suspended in the waster column and interferes with the test kit reading as the reagent will dissolve the fine particles, giving false reading, especially high Alk readings. However, the fine particle spreads on the bottom do act as "seeds" for settlers like coralline algae. Being that it is aragonite means it has about zippo Mg++. Mg++ does not fit into the aragonite crystal lattice hardly at all, as it has the wrong ionic radius to fit into it. That does not mean there is zero Mg++ in aragonite. Mg++ is more of a fit in ion in calcite and Sr++ is more of a fit ion for aragonite. And why you find high levels , so to speak, of Mg++ in calcite and Sr++ in aragonite.

 

[ZANYMASTER]

+1.Even the bottle says to have your PH to at least 8.2 for it to be effective.

 

[adamt]

I personally dont like that stuff, but I know a guy at an lfs and its all he adds to his reef display... his corals look like sh$% but he has the most purple rock I have ever seen in my life.

 

[Boomer]

Zanynaster

That stuff does not dissolve in seawater until your pH is at least in the low 7's

 

[ZANYMASTER]

That is kind of low.Are you sure?

 

[Boomer]

Let's think out side the box here. Think of a Calcium reactor where the pH has to be ~ 6.8 for it dissolve it. Now think of one with aragonite sand in their tank. If it dissolved at pH in the 8's your tanks would look like a clouded mess. If it dissolved at that pH how the heck could corals even grown. When one adds any kind of fresh aragonite to a system the pH, Alk and Ca++ actually all go down due to solution kinetics. This causes over growths, also called surface poisons, on the grains of the aragonite where Hi-Magnesium Calcite grows till there is an equilibrium. Lastly, if you look at aragonite rate constants, i.e, the amount dissolved at x pH over time it is about nil in any kind of NSW pH.

Is it possible at all to get around this...yes. Dissolution rates and precip rates are controlled by the pH Ca++ and Alk. These "rates" are called Omega numbers. If one looks at or calculates these out you will see that the Alk and Ca++ and Alk have to be very low and well below that of any reef tank. For example, it will start to take place with a pH of 8.2, Alk 1 meq / l (2.8 dKH) and Ca++ 340 ppm. If we now raise these to more of a reef tank levels say, 410 ppm and Alk 2.5 meq / l (7dKH) the pH has to be in the mid 7's for dissolution to take place.

The CarbiSea "Chemist" is very confused They get this 8.2 (actually they claim 8.3), which is not a pH at all but a FW pKs ( solubility product constant to the neg log base 10) value for aragonite. A pKs is a number that tells you how much you can dissolve, to reach saturation, not at what pH it dissolves.

Now for the "touch down". Tests have been run on these powdered aragonites.

Calcium Carbonate as a Supplement
http://www.advancedaquarist.com/issues/july2002/chem.htm

 

[Staaan]

Boomer, which calcium supplement do you recommend?

 

[Boomer]

Well, Stan, if your tank can do it then only one, Calcium Hydroxide, which adds nothing but Ca++ and buffer, unlike others that end up adding Cl- and Na+, which accumulate over time. Now, if we are to look at two-parts and you want to buy them off the self and not do a DIY then ESV B-Ionic or TLF C-Balance are all well proven.