Rock Bottom for reef - suggestions please

[johnmackay70]

I am setting up a 40 gallon breeder with a 75 gallon sump.

Sump will have a large portion of it set up with a DSB and refugium.

I was thinking about running a bare bottom display tank, but initially, this look always looks incomplete to me, so I have the idea of covering the bottom of the tank with a thin layer of rock, but I don't think this will look quite right using pieces of LR, so maybe making up some "aragocrete" and pouring a thin layer to cover the bottom of the tank (maybe 1/2" to 1"). I know, there will be a long curing process (40-60 days) for arogocrete. I think this could look great with a real set of LR on top - especially after the coraline algae builds up

I am wondering if I have to worry about expansion of the arogocrete (ie breaking the glass of the tank) or other possible problems that might be caused by this.

I am looking for info, suggestions, alternatives and opinions

Thanks!

 

[cr500_af]

Last year, when we had the meeting on aquascaping, the speaker showed some slides of a BB tank where the bottom was covered in LR rubble. It looked pretty cool and gave lots of foraging space for the fish. I would do that before I poured something in like a concrete product (which even if safe, you'd have to consider permanent).

 

[acroholic]

You could get yourself a piece of 1/8" glass to cover the bottom. Then you smear silicone sealant on one side, then press sand or crushed coral or whatever into the silicone. You can remove it if you ever need to in the future.

 

[morganatlanta]

I tried a similar thing to make an aragocrete background. I decided to go another direction, so the pieces are soaking in a tub in the back yard still, but I think it would work well for an alternative bottom. I'd definitely consider it.

If you try it, put thick cardboard dividers in to make the bottom into sections so that you can take the rock out to soak/cure it. You want decent size gaps between the pieces so that they don't completely interlock. The cardboard should give enough wiggle room. Make sure you don't have any pieces that span the whole width of the tank, or you'll have a heck of a time getting it out. Dividing it in 6ths or 8ths or so would probably work well. You can fill any gaps with foam when you finally put it in the tank for good. The smaller pieces would also be easier to fit in a tub for soaking.

When you mold the bottom, line the tank with a very heavy plastic bag liner to protect the glass. Line the whole thing, not just around the bottom, and be very careful when you take the pieces out. I put a couple serious scratches in my tank getting the pieces out after they had dried.

I used water softener salt in my mix to give some open cavities in the rock and lower the overall weight of the stuff.

I'd shape the bottom some rather than doing a flat 1/2" thick. I think it would look awesome having some hills and valleys, completely covered with fields of GSP, palys and zoas.

You'd probably spend only $40 or so on the materials, and it would only take a couple hours to do, so it's probably worth it to try it out.

 

[johnmackay70]

Margan,

thanks for the suggestions, I think I may try what you have described...I may even try to make some pieces to glue to the vertical surfaces of my overflow. I have a lot of thinking to do on this one.