[Great Reefer Man]

I have a 100g tank (48l x 24w x 20t). I have a single overflow (6" x 6"?) in the center. I have the return from my Iwaki wmd40rlxt pump split into two. One return in each corner. The pump is rated at about 1100g/hr at 4' head per Iwaki. The pump is backed off a little (ok to do per iwaki) and there are ball valves on each return and they also are backed off a little. I also have one MJ600 in the center.

My question is this. Is this enough current. I think it is proably about 800-900 g/hr. I recently tried to add 2 MJ1200's and it was WAY too much current. Everything was really really blowing around and closed up. I keep hear that with more current corals seem to grow better but I dont know. Maybe I have enough current. Any ideas????

[icemark]

I try for around 10 times per hour tank volume as a min. good starting point, although I have heard in nature it would be closer to 1000 times.

[Joe]

Dennis,

I have a 110g W/dual overflows. My return pump is a GRI 1500gph and it feeds one return line. I drive my chiller with a Mag 950 which feeds the other return line. That works out to around 2000gph at 4" of head. I also run four MJ1200's on a RedSea wavemaker. My current does not seem to be a problem. I think it's all in the placement. All my critters seem to do fine. I try to follow recommended placement regarding light and current. Sometimes you have to fudge a little unless you use lot's of epoxy to stick critters in place.

Joe

[Barry N.]

Joe if I were you I would try to get a little more current.

On my 180 I have a AmpMaster that provides 3000gph with 5'head, with my application I am doing approx. 2400gph with one corner overflow with 2 x 3/4" returns. Am also trying to stay away from powerhead in the tank so I have went with 2 gemini that each one provides 960gph. I have them on timers so that one comes on and the other one comes on when the 1st one shut down. One on each end of the tank. I sure like these pumps.

Barry

My Site: http://barryreef.homestead.com/index.html

[djheywood]

Nobody has mentioned this but it really also depends on what you have in the tank. you want 10-20 X per hour on a mostly SPS tank. these corals thrive under strong current (ie: crashing waves) but if you have mostly softies and LPS they don't necessarily like super strong current. In this case I believe 8X per hour is definitely fine. Bottom line, let your corals tell you. If they look great leave it alone.

Good luck.

[Great Reefer Man]

This is what Im talking about. I see that a lot of people have a lot of circulation. When I try to provide that in my tank....in any way....It appears to be too much current!

Dennis

[golfish]

Barry,
You only have 2x3/4" .... I thought you had more then 2 return lines....

Brian has brought up a very good point. it really depends on what you plan to keep. I don't see why your having such a hard time using Maxi Jet 1200's . I used to use them in my 55.

Mark

[Atkins]

Just as a side note i run roughly 1400 USgph in a 90 USG tank.
A few of the guys over here that run high flow SPS tanks reckon the maxijets give to harsh an outflow due to the bore of the outlet.
I recently added a Tunze 3000lph powerhead to my system. These tunze's have a 1" outlet and although really powerfull they give a nice even spread of flow across the tank.
Of course there is a downside as usual.......high price

I'm converting to a SPS tank at the mo but i do have some softs still and sgrooms and they seem to open fine.As Joe said... maybe some of the probs are down to placement ?

[Barry N.]

Mark, I have only 2 x 3/4" return coming back up my overflow box then then into split lock lines.


Barry

[golfish]

Barry,
2400 gph with 2x3/4" lines? Did I read that right. From what I have read the AM3000 wont do that much with 2x1" lines. This explains why your able to use that pump as a sump return and don't have the bubble problem.

[Ironreef]

per dolphin 1"=1200gph@4'. 1" into a y= 1800gph @4'. So 2 -3/4 I belive would be around the 1800 or less. Not 3000.

[Barry N.]

I never said I had 3000gph. Ironreef I do not have a 1", I have a 1 1/2" out of the pump and the pump is directly under the bulkheads. My 1 1/2" goes about 1 foot then into a 2" Tee and reduces into 2 x 3/4" flex that goes directly up the overflow box and then out (24")

Doing the math on the sump, knowing that 1" of sump holds 3.74 gal of water. ( 36"x24"x1" = 864 divided by 231 = 3.74 gal. If it takes 30sec to drop 5" that would be 18.7 gal x 2 = 37.4 gal in a minutes x 60 minutes = 2244gph. Now I could be wrong or my second hand on my watch doesn't work correct. Now that is the outside messurements of the sump so that would be a little bit less.

The ampmaster3000 w/ 5ft head will pump 3,000gph, according to their chart.

As far as bubble problems, the water coming from the overflow box ( 2" ) goes into a micro bag and then under a chamber wall then though 4" sponge then back, hard to have bubbles with that.

[Ironreef]

Yeah I'm thinking of an ampmaster but 3000gph was to much for my 120g. One overflow. I may y one of to a seaswirl and have on on a y to a loop. Still pondering. but fwiw I have had 2000gph @4' go through my 49g sump with no bubble no sponges no floss. Just a drip tray. For me I only get bubbles when using a sump thats to small for the turn over= not being able to keep the sump level 1/2 full. The drip tray helps slow the flow also.

[golfish]

Yeah, when I was using the am300 as sump return I too used the micron bag but I want a tank I can drive away from and come back in two weeks. The micron bag would clogged in two days, I would think the sponge would even be worse. Stuff like that has to be cleaned a lot or it will cause problems.

Barry,
Your getting more out of your AM3000 then I'm getting out of mine. I have 1.5" pvc going up half way splitting off too 2x1" PVC going to two 1" Sea Swirls. The 1" SS's can only handle 1150 gal each. I don't think it has anything to do with the SS's. I think it has to do with the 1" fittings....

Michael,
What do you consider "a sump thats to small for the turn over"

Thanks

Mark

[Ironreef]

I had my 120g hooked to a 30g sump= tank. The water in there looked like rapids. I hooked up the 49g wetdry. The water is calm don't notice it moving.The 20g of water in the 30g just moved fast and got pumped out to quick. Bigger or more water volumn doesn't do this. the sucking of water caused bubbles with the small sump. Not with the larger one. But this is just my observation one one tank. The 10+ extra gallons made a difference for me. I don't like sponges ,pad ect. or micro bubbles. I like to leave my tank for a month if needed.

[Barry N.]

Mark, I agree with you on the microbag but this is the only way I could control the return to the sump without throttling back on the pump. Yes I do have to change the micro bag and clean the sponges at least twice a week but it only takes me about 15 minutes to do.

On the other hand I might have to throttle it down as I still have some sand blowing around, thought maybe it might settle down by now.

Barry

[mastaJ]

OK, back to subject...Great Reefer Man, you never said WHAT you are keeping maybe that will help us. If I were you I'd shoot for 10x turnover rate. I also agree that placement is the key, because I have 30x turnover rate, and my soft corals are fine. HTH

[Great Reefer Man]

masta (huh!),

What I am keeping is a mixed bag. For LPS I have a grn opn brain, some trumpet coral, branching hammer and a hydnophora (lps or sps? It is long tentacle variety). I also have like 8 small SPS frags (2 staghorn, 1 mont. cap, 2 orange m. digitatas and 3 acros). As for softey, there are shrooms, finger leather, yellow figi leather, 3 or 4 colts, various groups of star polyps, sun polyps, two forms of pulsating xenia, various colonies of very rare and expensive aptasia anemones and various other polyps. I also have two T. derasa clams.

The tall colts and the branching hammer are the two that get hammered by too high of current. Also some of the large mettalic green frilly shrooms get bothered also.

Dennis

[mastaJ]

GRM, what i do is i place my PH, then i FIND a spot for my corals based on what they like...u are doing it the opposite way...which can be done...just find a good spot for you PH's that every coral likes OR move your coral OR forget about it... HTH