The one part of my frag tank setup I had the biggest problem with was getting the flow right. I knew I needed a lot of flow to keep the newly cut frags flushed clean to facilitate healing. Although I did not want to blow the frags out of the eggcrating. I opted to use one of the Tunze nano streams to get a decent wide and powerful, but gentle flow. It is easily pointed to adjust flow because of it's spherical shape. By the way, my frag tank is 33 gallons (34.75"Lx16.875"Wx13"H). Several of those out there producing frags on a regular basis use SCWD's (Switching Current Water Director) to double the output of a return closed loop pump for cheap. The original SCWD has 3/4" barb fittings, but the new SCWD had 1" threaded connections and a removable top for easy cleaning unlike the original 3/4" model. My last recommendation is to have a bare bottom frag tank. This makes it easy to clean the bottom of detritus and uneaten food... yes uneaten food, more info on that in another post. To still have a sand bed, set one up in your sump or refugium. Please post your comments and questions you might have about your current or future frag tank.
I've had a lot of time to think about how I'm going to set up my frag tank, since I bought it almost a year ago and still not set it up. I like the idea of the SCWD. I may try that, I plan on having a 30 gal. tank for a sump/fuge and skimmer compartment. I have a spray bar across the top that I was thinking of having the sump return feed it, with a mag 12. Then maybe a closed loop with a SCWD for alternate flow, I'll just have to be careful and not have to much flow on some of the low flow corals. The tank is 90 gal. with built in overflows. I have a 36" hamilton MH lighting system I may try and use. The fuge will have cheato, rock and sand, I'm kinda up in the air on weather to put sand in the main tank or not. On one hand it would be easer to keep clean, but on the other hand sand works as a good filter system and a good place to set your lower light requiring corals. I'm thinking basically like a normal reef tank, except no fish and no live rock in the main tank. Soon as I find a deal on a good skimmer, a mag 12 pump, maybe two I'll should be ready to get this up and running.
A frag tank seems like a great candidate to be bare bottomed along with a remote deep sand bed (RDSB) -- a five gallon bucket full of sand with water flowing across the top. Anthony Calfo promotes RDSBs as great nitrate reducers.
I have never been a fan of a bare bottom setup but I would guess that a frag tank would be the best application for one. I think that with a remove deep sand bed it would do great, I currently have a plenum in my frag tank, but that is just me - a fan of the plenum. I have opted for the ocean motions over the squids because they do not cut down on water flow at all. Although, I can not speak for the durability of the squid I have had to replace the motor on my ocean motion squirt after about 3 years which I felt should have lasted longer. Blake is correct about the flow - I am using a maxi jet mod on a wavemaker for flow and it has done really well. Please post you success with building frag tanks - I need all the help I can get.
