I wonder if you guys can help me out with an idea for an experiment.
In setting up my new tank(s) I've ordered some BRS dry Pukani rock. This stuff is awesome. It is really light and porous, but has the reputation for leaching phosphates over a long period of time.
Search "Pukani Dry Rock" and several suggestions will come about. Many have suggested various methods to deal with the phosphates:
1) Soaking in bleach prior to "curing" - the idea is to dissolve/remove some of the caked on dead organics that would slowly break down and release nitrates and phosphates.
2) Acid bath (muriatic acid or vinegar seem the most popular) - the acid dissolves the top layer of the rock, which is basically calcium carbonate. In doing so it releases a lot of the bound phosphates. The downside is it can also eat away a lot of the dry rock. It also requires special handling and ventilation due to the acids and the fumes created.
3) Slow cook time with lanthanum chloride (Seaklear) to bind phosphates. Most people add the Seaklear every few days while cycling the rock in a dark bin of saltwater
. The Seaklear precipitates the phosphate and does not appear to affect the curing or cycling process.
While there is a ton of anecdotal information, along with speculation as to what should and should not be done, no one has done a good head-to-head with the various methods (at least to my knowledge).
So, what I am proposing is a little biology experiment. Assuming these rocks do leach phosphate (something that would have to be measured with my sample first) I plan to take roughly 20-30 pounds and place into separate bins.
- One will be a "control" in which I do nothing but cycle the rock with saltwater
and follow a regular "curing" protocol.
- The next will be the bleach bin - soak in bleach about 24 hours and then follow the curing protocol.
- Next will be the Seaklear bin - bleach and then add Seaklear every few days for several weeks.
- Next, Muriatic acid bath then regular cure.
- Finally, the "extreme cooking/curing bin" with bleach, acid bath, then cure and if phosphates are still present Seaklear can be added.
The end point will be time to see a reduction in phosphates.
I know I will end up with WAY more rock than I need, but I thought it would be interesting.
Any thoughts or comments are appreciated.