[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: Source of PO4

For people looking for another source of  phosphates, you might consider
Carib-Sea gravels.  It appears that their marine gravels and also their
cichlid gravels not only leach carbonates into the water (which can be a
very good thing if you are injecting CO2), but also significant amounts of
phosphates.  I put about 10 lbs of  their Congo River Mix into nylon bags
and put the bags into the trickle filter of my 100 gallon planted cichlid
tank.  I had hoped to stabilize the KH level of the tank.  My KH didn't
change much, but the phosphate level went from 0 ppm to off the scale
(greater than 3.0ppm) in a matter of a few days.  Its amazing how quickly
algae will grow in a PO4 limited tank, when virtually unlimited amounts of
phosphate are released into the water.

Needless to say, I have removed the bags from the trickle filter and am
doing large water changes.  A quart of Kent Phosphate Sponge only made a
slight decrease in the phosphate level.

If you go to the Carib-Sea website, they have a page that shows the
phosphate levels for 3 of their marine gravels.  However, none of their
products appear to contain a warning that the gravel will leach significant
amounts of phosphates into the water.

Anyone want 20 lbs of slightly used gravel?

Best Regards,

Roger Gordon