Layer of crushed coral in refugium??

[Eboman]

Here's my thoughts.....

I currently have a bunch of Southdown in my sump which acts as my DSB (the main tank floor will be bare).

However, I'm trying to get some bio-diversity in the sump area. In the past, I've had great success with bristleworms, different pods, and all kinds of other critters when I've used a more coarse substrate (like pea-sized "gravel"). THe bigger "gaps" between the substrate particles seem to provide safe havens for those critters that I find advantageous. FOr some reason, the finer sandbed only seemed to propogate much less visible life (a few spaghetti worms and that's about it).

What I'm thinking of doing is keeping the Southdown as the DSB (which is currently about 5" deep in the refuguim) and putting a layer of "calcareous gravel" around 1" deep on top of that. I'm guessing (hoping) the Southdown will eventually grow anaerobic areas to reduce nitrate, while the coarser substrate will be a haven for various worms, pods, starfish, and the like. WHile I realize the coarser substrate will act a a detrius trap, I'm hoping all of the various "critters" will act as detrivores and keep things relatively clean. I'm also figuring the coarser material will keep the finer substrate in place in the event I get some weird flow surges in the refuguim area).

Does anyone have any thoughts on this idea?? Any drawbacks???

Thanks,
Eboman

 

[mr_X]

sounds good. i have about 2 pounds of golfball sized rubble rock on top of my sand bed in the fuge. some say it will be a detrius collection area, but i have a powerhead in the fuge, and i pour my top off water in there as well, by the gallon, so it kinda stirs everything up once a day.
i guess if i add an auto top-off i'll have to stir things up by hand once in a while, but i'm pretty comfortable doing it this way so far. i have a massive amount of life in there, as well as the display, and no water parameter issues as of yet. :wink:

 

[Len]

Sounds like a plan to me. Only drawback is if you ever plan on siphoning the sandbed, it may be harder to get to the lower levels. I do partial siphoning of my substrate from time to time, leaving the majority untouched so it will repopulate the siphoned half. Some people don't siphon at all though (I didn't siphon my old 120g's DSB for a decade).