Filterless?

[geekdafied]

If you run a bare bottom tank, with only corals. Have a powerhead for circulation. Regular dosing. Do you need to run a filter?

I have thought this for awhile now, and have looked all over the net. I am thinking of making a new frag tank and do it bare bottom, have some egg crate to keep the corals off the bottom. The only thing that would be a problem that I can think of is dosing.

anybody have any experience doing this, or could point me in a direction to find out?

[crumbletop]

Fishdoc11 runs his 120 barebottom, I believe. I don't think it would be a good idea to put eggcrate on the bottom, as this would create a bunch of pockets where detritus could build up. Starboard is what many people use instead. The barebottom folks also skim aggressively to keep waste out of the system. I assume you'd have LR in there in addition to the corals, 'cause you'll need some stuff to break down nitrogenous waste.

I'm not sure what you mean by regular dosing. If you are referring to dosing to keep alk and Ca in a good range for calcification, then it would be good to do that (or run a Ca reactor) whether you run barebottom or not.

[geekdafied]

The egg crate wouldnt be sitting on the bottom, I would attach 3/4" pvc pipe to it so there would be flow underneath it. You would be correct on the dosing. I will probally just use a plenum and be done with it. The tanks I plan on using are pretty shallow, thats why I wanted to run bare bottom.

[APFish]

I run barebottom. You have to turn over about 40 -50 times an hour. The detritus has to be kept in to suspension. Also, skimming is critical. I have live rock that I have cooked to do some filtering that is about it. Becareful of what you are dosing. You won't have the "sink" w/o sand. I do regular water changes and dose Kalk as top off that is it. I feed corals and fish once a day.

Rob

[geekdafied]

I was going to use 6" deep tanks to cut down on lighting expenses, but considering the tanks are going to be like 12.5g I should only need like 1-2" sand bed so I should be fine. Im going to run 2x65w pc lights on 12.5g so thats going to be a lot of lights for a little tank, and the light will be like 4-6"s above the corals

[Sir Knight]

That size tank IMO is going to be very unstable with heating cooling, evaporation, water quality, water movement, lighting. There is a point that sallow is good but when you take it to that extreme you may get into trouble very quickly.

Are you planning on SPS, LPS or softie?

You may have enough light (I am not a fan of PC's at all) but lets look at heat you are placing. You are talking about 130 watts of light over 6" of water that will heat the water very fast. Corals and the rock itself will produce waste, So water replacement on at least daily will be required, plus makeup water and some kind of cooling and when the lights go out heating.

For sand, again you only have 6" to work with, so water movement will more than likely blow it all over the tank or just pile it up somewhere. If you go that route why not look at a remote sand bed

I just don't see a cost effective way of doing this as far as long term stability. You may consider tieing these tanks together and have one central filtering system made up of sand, skimmer and live rock or get larger tanks that are a little deeper and just place the corals up high in the tank. either one of these would give you more water volume which in turn will make for a more stable environment.

Just may 2 cents.

[Angela Short]

My shallow frag tank was a real pain to keep stable with 130 watts PC over it. The SG would swing like mad. Stuff lived in there just didn't grow so for a grow out tank I would concider something else if it were me. The heat was also a issue.

[geekdafied]

Im just going to plumb them along with one of my 75g tanks. That fixes all of the issues basically.