Should I add sand to my BB 400g SPS tank?


New member
I have been throwing the idea around about adding CaribSea aragamax sugar sized oolite sand to my 400g SPS tank. This tank has been set up since Dec. 08 and at the moment is completely barebottom. I thought once the bottom covered with coralline algae that the look would not bother me. But this is just not so. I dont like the look of it at all. Besides the look I am also getting some areas under the rock that collects detritus. The tank has about 550lbs of live rock and I cant get good enough flow under the rock work without a closed loop in the bottom of the tank, which is not an option.

So I want to add a sand bed without removing the rockwork. This will likely mean that some area under the rock will have no sand at all. Could this be a problem? I dont want this area to act as a "pond" for detritus either. Just not sure how to get the bottom covered under the rock without removing the rock.

Another issue I have is I probably would be adding dry sand via a funnel in order to get it to the bottom without blowing everywhere. This means I am not going to be able to rinse the new sand. You see any problems with this?

I have 180lbs of new sand that I am going to start out with so it will be very thin in areas. Again you see any problems with this.

I have always keep a sand bed in my other tanks but decided to go BB with this one and I just dont like the looks.

I am not going to jump right into this without getting your advice first. So should I just leave it BB or would I see any other benefits from the sand other than looks?

I am open to all suggestions.

Thanks guys

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Sciencing Daily
theres no reason that you cant rinse it before you put it down the funnel. Also, you'll only want to add a little at a time, like a few cups a week untill youve filled it to wear you want.


New member
Has anyone started off with BB tank and went to sand bed later?
How did it work out for you?
How did you go about adding the sand?

Username I would think dry sand would flow through the funnel a little better. So what would I do rinse and let dry first?
And if I only added a few cups a week it would take 2 years to add all the sand. This is a 400g tank and I would probably need about 300 to 400lbs of sand. I was thinking about doing like 30lbs per week or more. Would added that much cause a problem?


New member
youll be better caribe sea special grade as is a little bit more than fine sand you could rinse it with RO/DI water and put it in your tank by hand
And it looks very nice and you dont get sand storm


Appalachian Reef Society
Premium Member
The trick is to get the sand released as near to the bottom as possible whether it be by funneling into a tube/pipe to the bottom or lowering it a bowlful at a time.
If even one handful is released near the top, all of the fines will end up in the water column as the heavier stuff sinks to the bottom.
Either way, I'd plan on a silty operation.


Premium Member
I just added 40 lbs of pure white sand from the caribbean to my 5 year existing reef tank. My current tank had a crushed coral bottom and I was wanting to add a layer of sand it to.

I pre soaked my sand for 24 hours, i then filled gallon bags full of sand and cut the corner off. I would then squeeze the sand out on the bottom of the tank. Got the idea from when my wife makes cakes and she uses bags to squeeze out toppings..

I had a slight sand storm that evening, but the next morning, tank was crystal clear. I did this to my 150 gal.


Premium Member
My advice would be to set up a few rubbermaids, add sand, saltwater, powerheads and some liverock.

Let it run as an independant system for a week or two.

This will allow a few beneficial things to happen.
1. You can filter out the super fine dust.
2. Bacteria will populate the sand making it "heavier" and therefore its addition will be exponentially less messy upon introduction to your display tank.

Just my $0.02



I'd frag it.
I would poke a hole in the bag, fill with saltwater, then submerge said bag into the tank, slit open the bottom, and slowly dump it out into your tank, with all the powerheads off. Should minimize dust and sand blowing around everywhere.

The funnel doesn't work well in my experience.


Premium Member
Premium Member
When I needed to add more sand into some awkward spots in my tank I cut the top off a large plastic pop bottle and poured wet sand through it into a flex piece of pvc pipe and I had good results.

matt the fiddler

New member
"Besides the look I am also getting some areas under the rock that collects detritus. "

what do you think will happen with sand? that will cut back on more flow, and cut back your ability to blow it out!!

can you describe your circulation, pumps- placement.. you might be able to indirectly get those areas via a "feed back loop" or barrel roll.

have you considered starboard?

also, putting sand in over the existing rock is a perfectly ok way to add sand, if you do... i mean, sand will work it's way to some of those areas over time


New member
If you are going to add sand to the tank, I use a bowl with a lid. That keeps the sand from going all over the place on the way down. Then I move it with my fingers to any awkward spots.