I'm sort of planning another tank and wanted to see if anyone here has run a deep sand bed in their display tank. Figured I'd pick someone's brain here since I can't post on RC any more (won't let me stayed logged in...no idea why).

What type of substrate did you use? Aragonite, Special Grade, sugar fine?

Have any issues with it being blown around in a high flow tank? I'm looking at about 6000GPH+ in the display.

Might be hard to do a deep sand bed with such high flow but I'd like to keep SPS along with fish like jawfish. Love to watch those little guys build and build. Plus the added benefits of a DSB.

I guess just post your experiences, good or bad, about them.

Hi Burks,

I used deep sandbeds in all my systems and really enjoyed their benefits (both bacterial and as habitat for macroinvertebrates) and their aesthetic appeal.  I used Sugar Fine Oolitic as a 3" base and then created a perforated surface using Special Grade and all the spoils from live rock boxes, mixed with as much rubble as I could get anyone to sell me. 

By having multiple grain sizes, you'll get sorting of sizes with corresponding velocities of the water column.  I never found it necessary to have 6000 GPH in my 125 gallon (nor would I want to deal with the heat), so you'll be in a realm of discovery there.  I might have had 2000 GPH, but I did it efficiently by placing all mixing devices near the upper end of the water column, so that by rotating the upper column, I also rotated the lower column efficiently and without any individual having to bear direct velocity.  Volume, not speed! 

I also moved the bed once without any tremendous problems. I had a lot of fine organic sediment settle out on the surface, which freaked me out at the time, but I siphoned it off, and viola, just like new.  I think it actually helped rejuvinate the bed, which gets to the criticism. 

One valid criticism is that over time, like any system with huge input and little export, it will entropy.  But I was amazed at how well it handled my ridiculous requirements.  I was dumping in 10 -12 oz of brine shrimp a week with a single purple firefish :)  I like to push the envelope.  I've yet to see the coral growth matched, but I haven't been exactly watching over the last 6 years for someone else to show their kung foo. 

I kinda go through some of it in a presentation I did for reefs.org.

Thanks Todd! I'll probably do the sugar fine base with the select top. Not a big fan of the sugar fine look so the select grade will serve many purpose for me. Looks, function, and keeping the sugar fine down.

You have to remember too that once biofilms have colonized the substrate, nothing really goes anywhere for long.  Even if you have a big powerhead fall down and blow straight into the substrate (which happened a few times to me with all that pocillopora growing on one of the recirculating powerheads).  When that would happen, there'd only be a slight cloudyness to the water and it'd be gone within hours of correcting the problem. 

Todd

I have a 3" sand bed ( carib sea reef grade) and have no problems except when I had a diamond gobi sifting it for the first couple of weeks it was a sandstorm but once all the dust got filtered it was fine. I would rinse it first next time.

Our display tanks here have deep sand beds of varying depths.

The 175 Gallon Bowfront has from 2''-6+'' in a wavy fashion. I was going to smooth it out, but thought it looked nice that way.

The 120 Reef had around 4'' of sand (now about 3'' or so from dissolving).

Pic isn't very nice quality (that's gonna need to change)

and our reef lagoon has a 9'' layer in it. Can't see the sand so picture won't do any good.

I remember a few years ago when a certain farmer planted this saltwater seed in my head.    thanks for the advise

Thanks Trilby and Timothy! Nice growth shots too. I noticed when I was in there recently you added two more fixtures to the 120. How has that T5HO done for you (obviously good)? Your thoughts in it vs MH?

Timothy, do you have high flow in your system? I can't seem to remember how it was. No issues after a while with blowing sand all over?

I didn't notice that much improvement over just the t5 ho's, but it seems to make it look prettier. The 120 goes back 24in, so it definetly helped lighten the overall tank. Before the halides were added the t5's were in the back 2/3rd's of the tank, now the halides are in the back and the t5's are up front.

I'll be getting a Fresh pic of the 120 soon. It's grown alot since those last pictures.

for flow it doesn't have a ton on it 2 eheim 1262's (approx 1800 gph total) hooked up to the install set 2's. Very LOW TECH TANK

Yet your zoanthid/paly growth is insane. That's my favorite part of the tank, zoanthids. I can't grow them in either of my tanks. They......."live" but never really grow well. *shrugs*

Yet I kept a Pink Birdnest in there for months before I killed it while moving it to another system.

I have pretty good flow with no blowing. I have a vor-tec mp40w a 700 gph return a mag12 closed loop and a korila 1 all in a 100 gal 48x18x26. the only blowing I have had is when I clean the glass and I hit the sand it blows around for about 5 mins then its good. my vor-tec is kicked up all the way on reef crest and has pretty good wave action.