Observation

[MitchM]

Originally Posted by reef_raf

..I'm guessing this implies the rock and sand were contributing a lot in the way of dissolved organics...

Hi Brad,

That's about it.
With a lot of life existing in the sand and the rocks, both on and under the surface, you now have a reduced bioload, basically. Detritus is formed by bacteria attaching to the DOC in a high enough quantity to a point that it's heavy enough to fall to the bottom and visible to our eye .
Steve makes a good point, plus the extra room in your tank helps keep the DOC suspended and gets it cleared out more effeciently, too.
IMO.


Mitch