Closed loop thoughts

[kwl1763]

Ok, I'm in planning stages for my next tank which is a 180 that I will setup in Feb.

I'm a little torn on the closed loop. First quick setup stuff.

It's a standard 180, coast to coast horizontal overflow, 3 drains. I will use a blue line 70 for the return hooked to 2 penductors. I am trying to have no powerheads in the tank (except a wavebox if that counts) though I realize there may still be a few dead spots I have to deal with.

So that leave me with a closed loop. The idea is I will have the input of the closed loop sucking from a long pipe in the bottom of the overflow (since the overflow runs the length of the tank should be no issue pushing a lot of volume through there (I realize this defeats the purpose of surface skimming a bit so I could be talked out of that one). Anyway my thought is to put an OM 4 way with 1.5 in and 4 1" outs. Run the outlets kind of evenly spaced to 8 3/4" locline outlets (front and back about 2 ft apart, probably the fan outlets) over the tank.

Wow a little more long-winded then I would have liked, to the point. I would really like to run a hammerhead gold for this setup. Basically 4 of the 8 outlets into the tank would be on at once so they would have roughly 1000GPH each coming out of them.

To much? I'm an SPS freak so want the flow and I want the 8 outlets so i can point and direct but is it going to be to much in a 180? I am going to have a shallow sand bed in there. Alternative of course would be to step back to a Dart.

Anyone ever actually use a hammerhead gold? I have used a few darts in my day but not the beast that is the Hammerhead.

 

[ss95003]

I had a closed loop on my tank and was not really happy with the flow. I had 2 outlets on the top and 2 on the bottom. The bottom was a 1" pvc pipe that had a bunch of holes drilled in it. I had a Dart driving it.

When I designed my tank I was going to go with 2 darts with 3 outlets each, 1 on top and 2 on the bottom. but then I just decided to go with Vortechs. I too did not want powerheads in my tank but I found the vortechs to a compermise because they had no cords in the tank.

My issue was the bottom spray bars and all just did not have enough flow. A dart will restrict and just push less water with pressure not force the same about through those holes. I think my plan b would have worked but I just did not want to chance it.

So personally I would scrap the spray bar you are talking about and if you go with the OM then get his 1.5" omni flex too and don't restrict the water flow.

Any minute now Wes should post on there that CL are old technology and not used any more but I disagree with that. I like the clean look of a CL as long as you plan it out correctly.

 

[kwl1763]

To clarify the spray bar is for the intake not the output. I do like the idea of the ominflex nozzles. I'll have at least 1000GPH coming throough each output (4 total on at a time) so I think 1" will probably be fine.

Still considering vortech but wow the cost !! I would need a minimum of 4 I think.

 

[DaveG99]

a couple mp40's are much nicer than closed loop in my opinion. You could also put a couple koralia 4's in the back corners out of the way if you need some additional flow than the 2 vortechs and want to save some cash.

A closed loop system heats up the water, creates more of a chance of leaks occurring, and also is a pain to set up.

 

[daveonbass]

I drilled my tank 6 times to make my closed loop. Once I got 2 mp10s I haven't used it since. Thankfully it only leaks a tiny bit each month...so there is a slow growing salt creep on the back of the tank. And I consider myself one of the lucky ones. So I would just invest in a mp40 or mp60 or two.

 

[ss95003]

@DaveG99 wrote:

A dart pump does not heat up the water any more then having a bunch of powerheads in the tank. More chance for a leak??? it uses the same type of bulk heads people use for a drain to there sump. You set up once and cutting PVC to me is pretty easy.


The spray bar for an intake I am not really liking. Just get a large inke like this: http://www.pondparts.com/subcat247.html. You can put a riser on it and hod it behind some rocks.

I have used a CL and MP40's. I like the clean look of a CL, but like the differnt settings of an MP40. If I had to choose 1 I would choose CL.

 

[DaveG99]

@ss95003 wrote:

While this statement is true in general it isn't true when your comparing it to mp40's. I have an mp10 and the part outside of the tank gets warm not the part in the water.

Look at most peoples reef tanks and see how many people use a closed loop vs a vortech or tunze pump. I think you will find very few closed loop users and the ones you do find are old school reefers. I personally have never used closed loop and dont plan on using a closed loop system ever. I figure the less holes in my tank the less a chance of something leaking. Plus resale of a tank with a bunch of holes in it could be tough if you ever decide to upgrade or downgrade.

 

[ss95003]

While I agree that more people use vortechs over CL, it does not mean CL can not be effective, nor does it mean people still do not build tanks with them today. Many large tanks still use them. If I planned a new tank over 180g I would use a CL.

And the vortechs do add heat. Touch the back of your vortech is it warmer then room temp(promise it is at 100%, and a lot warmer)? If so then it heats the glass which in turn heats the water. Agreed it would not be much, but neither does a dart, the warm motor is not in contact with water. I have 2 darts, 3 mp40's and 3 250w MH. My chiller never comes on. So if you do your tank right I think heat can be managed pretty easly. My tank also is no warmer then 79 degrees in the summer.

 

[E488]

Would not use a spray bar type intake for the cl. Consider two 1.5" intakes connect them with a 1.5"t before the OM, cover the two 1.5" intakes with bulkhead strainers. The extra intake gives you some protection in case something clogs one, dead fish, anenome, etc... Not sure about the intakes being in your overflow boxes. If you are using dursos in your overflow for main circulation pump you have issues with noise as water levels may fluctuate with the CL pump and OM cycling.

If using loc lines on OM returns keep the pipe size as large as possible. Loc Lines restrict flow. Consider the omni flex nozzles,they are adjustable like lock lines and will not restrict flow. You do not want any flow restriction in your plumbing, too much and you may create back pressure in the OM which causes noise/malfunctions in the OM. Penductors restrict flow as well, ok on the main pump but not on the OM. That goes for sch 80 fittings and pipe as well. Some use them as and extra precaution but the inside diameter is smaller than class 200 pipe and sch 40 fittings and the 200 psi rating is sufficient if you ask me.

Stick with the Hammerhead, its easier to fix too much flow than not enough.

If you are going to split the four OM returns into 8 loc lines why not just drill 4 more holes or come over the top of tank and get an OM 8 way they are just a few dollars more.

IMO closed loops have there place, larger show tanks. I like the clean look without all the power heads and wires. Not to worried about the nightmare stories of leaks and tanks draining, dont think it happens as much as it's talked about. OM is a great combo with closed loops and if planned out and done right you can get the random flow without looking at all the powerheads. If you have'nt already checked out the OM forum on their web site do so. It will help greatly with your planning.

Longwinded?

 

[ss95003]

i just reread your post after the last comment. agreed do not put the intake in the overflow. There are to many bubbles there. You will have micro bubbles all in the tank. You do not want any air introduced into the CL.