I have a 20+ year old acrylic tank that is looking pretty ugly on the front and sides due to a deep sand bed I had the first 10 years that scratched up the bottom 3-4" where the sand was. When I went bare bottom I took the tank apart (the aragonite sand had become cemented, and I had to chip it into pieces to get it out of the braced top) and sanded/buffed the tank, but apparently didn't do a good enough job at the bottom where the sand was. Now the coralline has a foothold such that I can't clean it (think I further scratched it in the years I'd scrape the coralline and encrusting corals gone wild). So I can't see through the bottom 1/4 of the tank, and I've got a lot of corals on the bottom I'd LIKE to see. So I'm thinking of ways to make a "new", false bottom, raising it up to near the top of the coralline I can't remove. I don't want another deep sand bed (works ok the first years, then becomes problematic), though I'd actually like a shallow sand bed for my burrowing wrasses (they now have substrate in ceramic bowls that blend in pretty well with the live rock).
Any ideas on how to raise the bottom? I was thinking of a plenum on stilts (I see 6x6 modular plenums on Amazon, with iffy reviews - and not for this purpose) with a shallow sb, some inert material in the bottom (3" of marble? marble chips covered by plastic with fine holes to hold up a shallow sb), or something else? Sorry for all the blue in the image.
Any ideas on how to raise the bottom? I was thinking of a plenum on stilts (I see 6x6 modular plenums on Amazon, with iffy reviews - and not for this purpose) with a shallow sb, some inert material in the bottom (3" of marble? marble chips covered by plastic with fine holes to hold up a shallow sb), or something else? Sorry for all the blue in the image.