I've been cooking rocks in a Brute for a while

[WhatCouldGoWrong71]

So for about 6 months now I have been cooking rocks in a Brute. I have about 100 pounds of that purple rock in there that I started with. I sort of use that Brute as a recycle can. ANYTHING that comes out of my tank (filter floss, etc) takes a dip for a week or two in the Brute. It is thriving with life, I feed it weekly and do random water changes every couple of months.

Here is where I may have screwed up. I did some sump work and had to take about 5 large rocks out of my sump and I stored them in the Brute. I now want to use them in one of my displays to make an adjustment to add some additional SPS.

Thinking I may do this tomorrow, I just went and tested the PO4 and it is .47 (I changed the water (90%) about a month ago..). It looks like the purple rocks are still leaching. I am shocked 6 months later they are still leaching. I have lanthanum chloride and can dose that, change the water tomorrow in the brute, but that won't speed the leaching process up will it? However, where I am concerned that I may have mucked up is, the rocks that I pulled out of my sump and stored in the brute, are they now going to leach PO4? Any way to speed the leaching process up?

 

[piranhaman00]

Put some power heads in there to move water around rapidly and slowly drip lanthanum , you can remove all phos very rapidly this way, the rocks will leach as long as the surrounding water is low concentration