thanks for sharing!Here ya go - there are two really, maybe 3 of them…
The bottom one, main sump. Saltwater mixing above, rodi only for the ato above that
The top one to trap bubbles and to gravity feed the skimmer, and hold chaeto
This one has some extra live rock and is where I qt the fish. It catches a lot of the detritus and is easy to siphon
Some photos of all the sponges and goodies in the rock. Most of this is over 20 years is my system. I pull it all out once a year or so to shake out detritus and to siphon out the bottom of the tank