Wanting to attempt a 20G SPS Only Tank...Possible?

[joem1cha3l]

Was going to give a 20G SPS only tank a shot as I let my 29G do its thing and grow guys. Is this too small or is it possible? Im concerned with MH evaporation issues on my 20G so can you recommend a good 30" T5? Also should I include a refugium or can I get by with just a sump? Thoughts?

[ludnix]

Lighting will be the hard part with the 30" length. You could do T5 if you did it in 2ft bulbs that were staggered to cover the length, otherwise the next option is 36" in which you have to deal with the overhang.

[Sisterlimonpot]

T5's will be a better choice for evap. and a sump will work just fine.

[phenom5]

That's what I'm doing at the moment.

I have a TEK 24" fixture, and it's plenty of light. I have to be very careful to acclimate new corals to the light.

No fuge for me, just a sump with a big skimmer (well, big for the tank).

My tank is open top, and evaporation can be a bit much, even with the T5's, but nothing an ATO can't handle.

[iFisch]

There's 30" fixtures out there by Current USA.


It's the Current USA SunDial T5 HO w/ Timers & LED Fixture. (4x24)

[RRaider]

30" fixtures use 24" T5's. I'm using a 24" T5 retro over my 30" 29g and it's more than enough light.

IMO frequent water changes are more important in a small system, but it's definitely doable.

[pusanpa]

It will be LOTS of work + hassle to make them happy and colorful.

To keep them happy and colorful, I recommend getting a bigger tank like 40breeder and spend some money for proper initial set up like ATO, decent skimmer, powerhead, sump, GFO reactor etc

[vangogh121]

This would be a pain in the arse to maintain. there is very little leeway with a tank than small

[redfishsc]

I have a SPS dominated 10 gallon with a 4X24 (yes, a bit of light overhang, but it overhangs the refugium).

I grow SPS in it fine, but I do not get the kind of growth that guys with 120's and such can get. I just swapped frags today with a friend that has an orange monti cap I swapped him several months ago, and it's bigger now than the parent colony in my 10g I broke it off from.


However, they do grow and look healthy.


You will need to stay on top of water top-offs. EVERY MORNING I check my tank. Most of the time I check the water level, and if it's 1/4" or more low, I top it off. Every second or third day I check the salinity with a refractometer.

I have a ~3 gallon refugium and two small fish.



I recommend the sump with a small skimmer. I built a DIY skimmer for my 20g frag tank that I will soon connect to my 10g. I personally think once I have the 10g plumbed in with the skimmer, things will pick up in growth.

My 20g is mostly for growing softy frags, and it has a 4X24 over it. The light on the ends is fairly low but I'm pretty sure that you could grow montis and such there, not to mention mushrooms and zoanthids.

Originally posted by pusanpa
It will be LOTS of work + hassle to make them happy and colorful.

To keep them happy and colorful, I recommend getting a bigger tank like 40breeder and spend some money for proper initial set up like ATO, decent skimmer, powerhead, sump, GFO reactor etc

Other than the initial setup cost (light and cost of the tank) I agree with Pusanpa. A 40 breeder is a SWEET tank for SPS. A Nova Extreme Pro 6-tube or a 4-6 tube retro kit will work great over a 40b.

[unbreakable]

just buy an AGA or aquaeon 20g long or tall and drill it. buy the overflow kit from www.glass-holes.com i agree a 40g breeder would be better, but i dont see why you cant in a 20g. i just see flow being an issue

just buy an auto top-off and put it in your sump. youll evap water with either light you choose

[therealfatman]

As long as you have a ggod size sump so as to provide stable thermal conditions and feed only lightly with a good quality food, preferably live, and keep those filthy fish out of the tam nk a smll SPS tank is easy to maintain, but keeping stable levels of calcium, alkalinity and magnesium is of course more difficult as typically smaller tanks usually hav a larger coral mass in them per water volume then larger tanks. Feeding frozen foods most often means using GFO is pretty close to manditory, fish neraly alwys mean GFO (good reasion to leave them out of SPS tanks as they are filty creatures). I would not consider a small SPS tank without a skimmer or continous auto water changes. A small Halide is OK as long as you have a large sump. At least a 20 gallon tank and 20 sump with a 70 watt halide. Not a hole lot of biological filtration is needed wiyh a SPS only tank. A couple pieces of live rock and a 2-1/2 inch sand bed would be great.

[therealfatman]

Don't forget circulation is very important with SPS corals. Most of a SPS's wastes are consumed by its symbiotic algae, called zooxanthellae. However the SPS emit mucous. The mucus released traps organic matter from the water column and carries nutrients to the sediment, forming a biocatalytic mineralising filter, and that the mucus contains up to half of the carbon produced by their symbiotic algae. This carbon readily becomes and energy source for denitrifying bacteria in the sand bed.

A single square metre colony of Acropora on the Great Barrier Reef can produce 4.8 litres of mucus every day, and 56-80% of this becomes dissolved in the water and filters through the substrate. The undissolved component of the mucus traps suspended particles in the water and picks up so much carbon and nitrogen that the levels increase by three orders of magnitude in just a couple of hours.

However, the mucous must be swept free of the corals, hence the circulation.

Ie. SPS corals are much, much cleaner reef tank occupants than fish and when kept alone are really quite esay to keep even in fairly small systems.

[redfishsc]

Fatman, how small of a tank (incl. sump volume) have you kept SPS, and how did they grow?


I did not realize how much mucus corals produced on a normal basis. I knew they'd slime up when fragging, though.


Believe it or not, I have run my 10g for the past 7 months with no skimmer. I will be, hopefully this week, plumbing it into my 20g tank, which does have a skimmer. I'll see if that changes growth rates-- I suspect it will.