building a frag tank - with just a closed loop and no skimmer?

[agoutihead]

what do you guys think? this is my design and idea...
im basically going to build a 40 breeder out of acrylic...
36Lx18Wx12H
i want to keep LPS and SPS.
im going to do the lighting as so...
on the LPS side i want to put 24" T5 10k (do T5's have the same kelvin rating as Metal Halides? also, do you think 2 - 24" bulbs will be enough over an 18" wide tank, or should i do 4?
and then in the remaining 12 inches im going to reserve for SPS. im going to do some type of double ended HQI 150w Metal Halide in 10k.
i figure i need more room for softies since they grow quicker. plus the T5's only come in 24"
i would like to do a closed loop on this system with no skimmer, 1) to cut back on start up costs and 2) less things to have in the way 3) is one even really needed if you do a weekly water change on a frag tank?
i plan on having two returns in the back top of the tank on both sides. on the left under the T5's i am going to have a slow to moderate flow for LPS. and on the right under the metal halide i am going to have a high flow for the SPS. all being controled with ball valves to aquire the proper flow rates i want. i am then going to have the drain in the bottom middle of the back panel.
so what do you guys think? with the way i have it designed, is it possible to do both LPS and SPS successfully in one frag tank? without having to use a skimmer if i do the weekly water changes?
i plan on putting a bulkhead in the bottom somewhere for an easy drain of the tank for water changes and will try to incorporate an ATO.

 

[maxalmon]

The no skimmer part would be a problem, sps like pristine water, can't imagine a frag tank without one, even doing the weekly water changes would help, but the cost of salt and time would add up to more than a basic skimmer like a super needle wheel, could be done without a skimmer, but a lot more work IMO.
Would it be possible to extend the tank to 48", this way you could go with 2 MH pendants and that would give you total coverage.
Good luck and keep us posted.

 

[zeroc]

has done some research about using skimmers on frag tanks. I'll try to find the link. But in short they got faster growth just using a skilter once in awhile. and leaving a good amount of protien in the tank.

 

[zeroc]

Here's a copy of the article.
Coral growth vs. coralline growth and the lack of skimmers.
Home coral farming reseach report G.A.R.F.
For the past 14 months we have been doing an experiment to see how the growth of corals would be affected by removing the skimmers from our systems. We have recorded the changes and we are now adding SeaCloneTM skimmers to one half of the the systems.
Experimental design
We have several coral farming aquarium systems that were started in October, 1995 using various skimmers. These systems were changed during 1998 until only 2 of them had skimmers. Everything else about the systems was unchanged. These aquariums consist of seven 55 gallon, three 105 gallon, and a 360 gallon coral propagation tanks.
Expected results
Removing the skimmers was expected to increase the growth rate of soft corals because we had found that the growth was often limited by lower nutrients in the water. We were interested in finding out if the sps corals would grow faster.
Results of primary experiment
Soft corals in the test systems did produce many more cuttings as the water started to load with nutrients. At the end of 10 months the growth peaked. We found that the growth rate of many of the sps corals was better. The growth of many strains of Xenia was very much better.
Second part of experiment
After the end of the first 10 months we decided to push the limits of the systems. We started feeding frozen Brine Shrimp and flake food in increasing amounts. We used as much food in these systems each week during August and September 1998 as we were previously using in three months.
Expected Results
We expected the color of the sps corals to turn to shades of brown as the internal algae balance shifted. We were preparing for stage two of the experiment - skimmer installation - and we wanted the nutrients to be as high as possible.
Each system was overfed until noticeable green algae was present. All corals continued to show increasing rates of growth until the algae stage was reached At this nutrient level the colors of the sps corals suffered.
Unexpected results
As the growth of corals increased we noticed that the growth of coralline algae was slowing. The nutrient level that gave us the best production rate in all of the corals had the reverse affect on coralline production. We are certain that this was because of the increased Phosphate levels. Other nutrients may have had an effect.
Second part of the experiment
We are now adding SeaClone skimmers to 1/2 of the systems. We will continue to feed at the new rate for 12 weeks. The new skimmers are the only change we will make in any of the systems.
Assumptions we have made
Coral production can be increased by decreasing skimming and coralline growth may be retarded. The brown color seen in many sps corals may be masking of pigments by internal algae.
Next step
We are setting up tanks to grow coralline algae on our rocks and reef plugs before we mount cuttings. These tank raised live rock tanks will be skimmed more to increase coralline algae growth. Corals will be added to each tank from the same parent colonies and 1/2 of the skimmers will be removed again. We will move some of the finished brown sps corals to skimmed tanks to clear up color after they are grown to salable size. We will keep records so we can find out if this faster growth and clean up time results in more production of quality sps corals.
We have taken a set of pictures of all of the tanks we are now skimming. We will soon be able to see if this one change increases the coralline production. We may start to set up separate systems for a three phase grow out of corals.
System # 1. heavy skimming to coat plugs with coralline algae.
System # 2. no skimming to promote rapid growth of cuttings.
System # 3. Skimming and adjustable lighting to clean corals for sale --
Summary
After four years of research on small scale coral farming we believe that moderate skimming of coral grow out aquariums will produce the most balance results. Growth can be increased by using no skimmer in many systems We are certain that there are more natural food organisms in the aquariums we do not skim. This increase of food and the increases in nutrients can result in much more production.
LeRoy Headlee
GARF
11/14/98

 

[agoutihead]

well i wanted to do the split of the lighting on purpose. but apparently, this isnt a good idea. someone else on another board said to not use T5 lighting because alot of people dont use them and it would be better going with just metal halides because thats what most people have and the switching of lighting may affect the frags in a negative way.
but dont alot of people use T5's? and besides, couldnt you acclimate them to either T5's or MH once you got them in your tank like your supposed to do?
since sps require the skimmer and lps/softies really dont, and since lps/softies grow quicker, i think im going to set up a lps/softie frag tank first, then with the proceeds, possibly start up an sps tank. sps is cool, and there is alot of money in it, but they dont really grow fast and i like lps/softies better anyways.
so with that being said... maybe i should set up a 30" tank just for lps/softies with one big MH above it? maybe a 250?
is it better to do a 250w and raise it up higher, or is it better to do a 150 and keep it closer to the tank?
i could possibly still do the 36" and do 24" of T5's and 12" of Mh if its good to do the lighting combo?

 

[reefkprz]

I'm going to use PC lighting and no skimmer on my softie frag grow out tank. I dont see the need for a skimmer unless you really want one I figure Large water changes on a small tank should be sufficient. (though if I had one I might use it but I am not spending money on a new one)

 

[agoutihead]

now that i think about it, i might just do a 30" tank with one 250w Mh raised up high enough to cover the whole tank, yet still being bright and effective enough to hit the bottom of the tank. whereas if i have a 150, i will have to put it closer and not get nearly as much light spread from side to side covering every corner in the tank.
would 1-250w MH be enough space for a tank of 30Lx24Wx12H?
im just a closed loop and no skimmer, probably even no sump so it doesnt need to take up as much space.