Negatives of Display Refugium Deep Sand Bed?

[Husker]

I'm planning out my 55 gallon display refugium, and I want it to have a lawn of seagrass (turtle, in particular) in addition to macro algae on the rock worm. This will require a DSB of 6"-8". I'm nervous about the idea of a deep sand bed, because of the problems they can cause long term. However, would keeping the deep sand bed in the refugium, away from the display tank, have any of these negatives?

I'd love to here some thoughts on remote deep sand beds in refugia.

 

[saltyfilmfolks]

I think fear of DSB are a bit overblown IMO. Fear in general of most stuff is pretty common in reefing (xenia). And long term is subjective. MANY have used them for a long time with no problems, but styles change and tech advances.

Check out my friend @Wiz tank. https://www.reef2reef.com/threads/wizs-75g-30l-fuge-29g-sump.264312/

 

[Wiz]

I've been running a 6-inch sandbed for about 5 years now. Only in my refugium. My tank has less than half an inch. All I would suggest is making sure that your refugium is able to be separated. Cut-off valves or whatever. And that is only in case of an extreme emergency. I have never needed it.
In my opinion it is just important to know what you are doing with a deep sand bed. Not just a light read of one article but a lot of reading. Not only articles but experiences that people have as well. Take those with a grain of salt though because you don't know what they did or did not do.
The main concern with a deep sand bed seems to be letting things out of the sand bed into the water column if disturbed. I have Disturbed my bed a few times by necessity and have had no ill effect. I have not stirred extensively but I have killed off parts of the bed on accident. As long as most of the bed is healthy it should recover. The danger comes when your sand turns black. You will see it happening. I do not mean the color on the top inch of sand as that is just algae caused by light, trapped between sand and glass. But large black areas which are dead and decaying materials trapped in the sand. In a healthy bed they will get eaten by the live sand and naturally recover. But it is possible to kill the entire bed. If you disturb the black areas and let that into the column, I am guessing that is where your trouble will start. I have never allowed this to happen. I did kill one corner of the bed when planting a mangrove. Took a while but it recovered. And actually about 20% of the bed when I move the tank to my new house. Which also recovered after a long time. But the black part will come on slow after disturbing it. So as long as you do not disturb it again and allow the bed to heal itself I believe it is okay. Or at least that is my experience.
I have no issues with my bed and in my opinion it is an integral part of my tank. Especially being that all I use is a small amount of carbon. No other filtration other than the skimmer. So the 30 gallon refugium is very very important. but this could be case-specific.
Bottom line is that it is definitely doable as long as you know what you're doing. As with most things in reefing.
I wish you luck with whichever you choose. And if there's any questions I can answer or try to anyway let me know.

 

[Husker]

Thanks for the comments and link. I have seen that build thread before in my planning. It isn't that I necessarily want a DSB, it is that I would like to have turtle grass and the two are necessarily linked. I'm getting the impression that it will be fine. I actually had a DSB in my refugium of my 75 gallon tank with sugar grain sand, back when that was the cool thing to do. I never had any issues with the tank being up for a couple of years (aside from a few floods from my HOB overflow), but that sand sure was nasty when I took the tank down.