Cecil, got a figure on how many miles/hours particulate matter that we would want out of a tank as soon as possible will hang around in the tank, while on the trip will it be breaking down into dissolved solids on the journey?
Saw some Physics stuff a few years ago where they were marking stuff with dye and tossing it on a puter to see what actually happens in a round tank with fish poo and solids in it. It was the centipede
flow you keep mentioning.
Oh sure there will always be particulates breaking down into small particulates. The trick is to keep it as minimal as possible. As you know the worst thing you can do is use a pump inside a fish tank which might as well be a high speed chopper! That's why I like my siphons as they gently remove suspended solids 24/7 via gravity and trap them in the clarifier.
The ultimate would be to run the bottom drain and a side filter (Cornell dual drain or Eco trap) continuously to a filter that takes the solids out immediately like a rotating drum filter or a sieve wedgewire filter. Unfortunately for my small scale systems they are out of my price range and would be overkill for my smaller fish loads.
I believe I saw some research on the Cornell Duel drain that showed a residence time of 10 minutes for solids? They used some beads with the same specific gravity to do the research.
I watched a pinched pellet that was laying on the bottom slowly makes it's way to the center drain.
