Filler for raised sandbed?

[I_Got_Crabs]

The aquascape in my new standard 65 gallon tank is going to involve two tiers of sandbeds. The high sandbed will be approx 1/3 of the length of the tank, "contained" by a cliff or wall of rock approx 8-10" tall, with the other 2/3 being a regular sandbed on the bottom on the tank. I haven't seen anyone else try this, although I'm sure someone probably has. I will call it "the poor man's drop off tank" if I can pull it off. See my rough sketch of a similar idea that involved three beds for a sense of what I'm talking about.

What are my options for filling the deeper/raised sandbed? I obviously do not want a sandbed that is 8-10 deep. I was thinking of making a 6-8" foam bed with the pond foam I am going to use for the foam wall background, but I am concerned about buoyancy. Any ideas?

 

[OrionN]

DSB is fine. I have had 10 inch sand bed without problem before. If you don't want DSB, you can use eggcrates and wrab it with a mesh and use this as filler up to the height you want and then add 2-4 inches of sand on top of this. A plenum chamber ( as in Jaubert Plenum System, a filtration system popular in the early 1990's) type filtrattion. This is fine too but I would recommend just straight deep sand bed.
Why don't you want a DSB? They are much more effective in keep your nitrate essentially 0.

 

[I_Got_Crabs]

DSB is fine. I have had 10 inch sand bed without problem before. If you don't want DSB, you can use eggcrates and wrab it with a mesh and use this as filler up to the height you want and then add 2-4 inches of sand on top of this. A plenum chamber ( as in Jaubert Plenum System, a filtration system popular in the early 1990's) type filtrattion. This is fine too but I would recommend just straight deep sand bed.
Why don't you want a DSB? They are much more effective in keep your nitrate essentially 0.

I would prefer a DSB in terms of aesthetics and practicality, but it seems like for every proponent of DSBs there's another person who claims it became toxic and nuked their tank. Like this thread:

http://www.reefcentral.com/forums/showthread.php?t=2268433

Has there been any decisive research or findings about this? Just not sure it's worth the risk if there is another way to reach my goal. Thanks for the other ideas btw. I will read up on the plenum system.

 

[OrionN]

I had it 10+ years, with a lot of diggers, no problem. I cannot speak for other reefers but I have no problem with it. DSB is very effective in eliminate Nitrate. I used them all. DSB, shallow sand bed, plenum, and Bare bottom. I keep marine aquarium since 1980, and I can tell you from personal experiences that DSB system is more stable, unless power supply disrupted. DSB have a huge amount of living organism that consume a lot of Oxygen and will crash quicker in the event of circulation loss.
Just set up my 320 about 6 months ago. Deepest part is about 6+ inches and shallow part is bare bottom covered with coarse layer of large rubble. I would not recommend DSB unless you have a sump so O2 does not ever get low at night.

Also most people who have problem with DSB have a relatively sterile bed. In nature sandbed is FULL OF ANIMALS which is what I have in my tank.

 

[Skedaddle]

Not to enter into the DSB debate but could you put something solid, non porous down. For example almost every town has a glass shop mine also does Plexiglas. You could go to the glass shop and have them cut you 10 or whatever, pieces of glass or acrylic, then just stack them up. Cut them smaller than the actual footprint you want so the sand can cover the edges along the tank glass. If you want 5" total height cut enough material to give you 3.5" and then put 1.5" sand on top. That way you would not need to worry about a nutrient sink if that is a concern. My experience is that the glass shop will sell Plexiglas scraps real cheap, they just want them out of their way.

 

[I_Got_Crabs]

I had it 10+ years, with a lot of diggers, no problem. I cannot speak for other reefers but I have no problem with it. DSB is very effective in eliminate Nitrate. I used them all. DSB, shallow sand bed, plenum, and Bare bottom. I keep marine aquarium since 1980, and I can tell you from personal experiences that DSB system is more stable, unless power supply disrupted. DSB have a huge amount of living organism that consume a lot of Oxygen and will crash quicker in the event of circulation loss.
Just set up my 320 about 6 months ago. Deepest part is about 6+ inches and shallow part is bare bottom covered with coarse layer of large rubble. I would not recommend DSB unless you have a sump so O2 does not ever get low at night.

Also most people who have problem with DSB have a relatively sterile bed. In nature sandbed is FULL OF ANIMALS which is what I have in my tank.

Thanks for the information, especially about the higher O2 consumption. Strongly considering a DSB now

 

[I_Got_Crabs]

Not to enter into the DSB debate but could you put something solid, non porous down. For example almost every town has a glass shop mine also does Plexiglas. You could go to the glass shop and have them cut you 10 or whatever, pieces of glass or acrylic, then just stack them up. Cut them smaller than the actual footprint you want so the sand can cover the edges along the tank glass. If you want 5" total height cut enough material to give you 3.5" and then put 1.5" sand on top. That way you would not need to worry about a nutrient sink if that is a concern. My experience is that the glass shop will sell Plexiglas scraps real cheap, they just want them out of their way.

That's a great solution. Dont know why I hadnt thought of it myself, I'll look into it.