to bio-pellet or not to bio-pellet

[Simons]

Just a quick note on PO4. I don't think many people know that there is actually two types of phosphates, Soluble reactive Phosphates (SRP) and Organic Phosphates.

When you are measuring the PO4 levels in your tank you are really only measuring the SRP phosphates, which are NOT the phosphates that 98% of algae like to eat. Those are the Phosphates that are dissolved in the water column, the 'bad' phosphates are the Organic Phosphates which are bound to the organics in your tank (ie rocks, sand etc). Those you cannot measure with any simple home test kit.

So just because you have a 0 or very low reading on your phosphate test kit, does not necessarily mean you have 0 phosphates.

That being said, if you are not having an issue with algae now, as long as you don't over feed your tank, do regular water changes you should be fine. No reason to add another piece of equipment that will likely have little value overall to your ecosystem.