tkeracer619
New member
I honestly would be surprised if your rock has much more to leach. It definitely takes longer then what you gave it during the curing process but at this point its been in the tank for 8 months it should have already leached out for the most part.
What does the tank read in po4?
What test did you use to determine that the pukani had 0ppm po4 before you added it? Most of the leaching occurs very slowly after the initial curing period and with a good amount of gfo to strip the water down it could take a few days for a normal test kit to show phosphates once the gfo is removed.
At this point I am not sure I would do anything to it other then remove it and give it a good scrubbing as well as keep up with gfo in the display. I really doubt there is a significant amount in the rock at this point to warrant removing the rock and retreating it. I would treat the entire tank with gfo as any phosphate that leached probably got sucked up by the rest of the calcium based rock in the tank.
Pukani is incredible rock but requires proper curing or you get this problem.
For GFO to be effective you need to drive the tank down to low numbers and then keep it there. This requires a test kit that can read down to low numbers so you can tell when the po4 concentration starts rising. I recommend a Hanna ULR 736 phosphorus checker.
What does the tank read in po4?
What test did you use to determine that the pukani had 0ppm po4 before you added it? Most of the leaching occurs very slowly after the initial curing period and with a good amount of gfo to strip the water down it could take a few days for a normal test kit to show phosphates once the gfo is removed.
At this point I am not sure I would do anything to it other then remove it and give it a good scrubbing as well as keep up with gfo in the display. I really doubt there is a significant amount in the rock at this point to warrant removing the rock and retreating it. I would treat the entire tank with gfo as any phosphate that leached probably got sucked up by the rest of the calcium based rock in the tank.
Pukani is incredible rock but requires proper curing or you get this problem.
For GFO to be effective you need to drive the tank down to low numbers and then keep it there. This requires a test kit that can read down to low numbers so you can tell when the po4 concentration starts rising. I recommend a Hanna ULR 736 phosphorus checker.
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