Personally I've been considering converting to a reverse-flow undergravel setup on my own tank. I've recently tried this on my 15 gallon freshwater as an experiement, & am utterly impressed with the results. Basically, think of the substrate as 'detritus repellent'. I wouldn't say nothing accumulates in it, but its only a fraction of what I would have expected without it.
My current substrate is about 2-3" aragonite, & I hadn't realized quite how much gunk had accumulated into it until I placed a couple of tube anemones. My idea is to take up all the substrate, lay down some undergravel plates, then lay a layer of 1/4-1/2" crushed coral over that & then replace the aragonite. I'm thinking the larger substrate layer in between the aragonite will help prevent the aragonite from working its way into the undergravel slots. The only quesiton I have then is just how strong a powerhead would I need to make sure there's sufficient pressure to force water through it properly. I have a couple small sandsifter stars in there, so I think that as they went around & overturned the substrate, they'd free up whatever pockets of detritus might build up & then it could go up into the water where it could be taken out by more traditional mechanical filtration (ie: my Eheim cannister). Thoughts?
My current substrate is about 2-3" aragonite, & I hadn't realized quite how much gunk had accumulated into it until I placed a couple of tube anemones. My idea is to take up all the substrate, lay down some undergravel plates, then lay a layer of 1/4-1/2" crushed coral over that & then replace the aragonite. I'm thinking the larger substrate layer in between the aragonite will help prevent the aragonite from working its way into the undergravel slots. The only quesiton I have then is just how strong a powerhead would I need to make sure there's sufficient pressure to force water through it properly. I have a couple small sandsifter stars in there, so I think that as they went around & overturned the substrate, they'd free up whatever pockets of detritus might build up & then it could go up into the water where it could be taken out by more traditional mechanical filtration (ie: my Eheim cannister). Thoughts?