Sump layout and Baffle spacing?

[Setec]

I am building a new sump for my 180g. I think I have the design pretty well set.

My main question is this. The return pump is a Sequence Dart. At zero head they are 3600 gph, so I am assuming maybe high 2000s to low 3000s once I get the pump fully loaded as it is feeding my entire system.

My sump is going to be 36x20x16 with about 11 inches of water during operation. inside of the sump is a 10x20x16 refugium. So the water path from the drain to the return pump is 10 inches wide.

I am planning on 2 sets of baffles between the drain and the return, one to separate the drain section from the refugium/skimmer return/chiller return section and another between the above section and the return pump.

In order to not make the baffles micro bubble creators / vortex generators, what would the recommend spacing be between the bubble trap sections? I was thinking an over/under/over trap with each section 1 inch a part and each baffle section would be 10 inches a part.

I can include a picture if it helps, but I just want to make sure that the spacing on the traps is not too small.

Thanks for any insight.

[Jefe12234]

That is WAY too much flow through your sump. Why not use the dart as a closed loop pump and use something much smaller for your return pump. You will never get rid of microbubbles with 3000gph moving through that size sump, and it's completely unnecessary for filtration.

[seagirl]

Originally posted by Jefe12234
That is WAY too much flow through your sump. Why not use the dart as a closed loop pump and use something much smaller for your return pump. You will never get rid of microbubbles with 3000gph moving through that size sump, and it's completely unnecessary for filtration.

i agree 100%. if your flow thru the sump is where it should be you don't need OUO baffles, they just take up room. I don't use them and have no microbubbles.

[scotmc]

Here is the info. you are looking for.It's under sumps.
http://www.melevsreef.com/

[Setec]

I have seen several systems that use the Dart as a return pump. I am not using it strickly to pump water to my tank, I am having it feed a bio denitrator, calcium reactor, refugium, a reeflo 200 skimmer and then finally my tank.

I have 5 splash down drains in my sump + the return from the phosoban and carbon reactors. With all of that movement, I dont see how you could get away with not having baffels regardless of how slow the flow was.

I figure I at least need 1 bubble trap before the bulkhead that feeds the return pump.

I looked over Melevs site and the one plan he has sets the baffels 1 inch apart. This is where I originally had my spacing, but I fear that is too close together for a sump of this size.

[sjm817]

1" spaced baffles wont do a thing for MB especially with a high flow sump, nor will a bubble trap spaced farther. If anything it will make it worse.

This has been discussed on many threads. Here is a recent one:
http://www.reefcentral.com/forums/sh...readid=1309598

[Setec]

Dart
tank size 100-200
Rate with 0 head loss 3600gph
Rate with 4’ head loss 2820gph

This is direct from the manufacture.

I chose this pump because I was told that was the pump I needed to feed a 180g tank with all of the other items hanging off the return line.

My tank specs claim it can handle 1600 gallons and hour in the over flows. My skimmer needs 400gph fed to it, and I am figuring on around 200-300gph for the refugium.

Assuming 9-12 feet of head loss due to pipes and fittings, I am thinking the pump will be moving around 1800 to 2000 gph. So I wont be fully feeding the tank after I feed the skimmer and refugium.

I currently have the same set up running but all done with mag drives and a smaller sump. I am increasing the size of the sump by nearly 20 gallons and dropping 3 mag drives for 1 external pump. Currently I have 2 mag 9.5s and 1 Mag 18.

I plan to put filter socks on the returns and the skimmer drains.

I am getting that the OUO trap does not work. So just 1 single baffle from the skimmer return to the drain pump sound better?

How does 12 inches of water sound with the pump feed at the bottom?

[Setec]

I forgot to add, I have plans on having a shut off valve inside the sump going to the pump. So if I so desire, I can valve back the pump to the flow that I need, also my return line has a loop back or water diverter valve that when opened will send all, some or none of the water from the pump right back to the sump. This too will control the flow of the system.

[Jefe12234]

The flow passing through your filters is not consumed. It goes in one end and comes out the other, so you don't need to have 400gph for the skimmer plus an additional 200-300gph for the refugium, etc. You only need the highest flow requirement (400gph in this case) moving through your sump. That 400gph will pass through your skimmer and your refugium, satisfying both their requirements. Now you can obviously run a little more than that to be sure you're not underdriving anything, but 2000gph is just unnecessary. With enough filter socks you may be able to control microbubbles, but you would get more flow in your display tank where you want it by using the pump as a closed loop, and using one of the Mags for your return. Also, if your overflows can only handle 1600gph, then 2000gph will exceed that flooding your tank.

[scotmc]

Originally posted by sjm817
1" spaced baffles wont do a thing for MB especially with a high flow sump, nor will a bubble trap spaced farther. If anything it will make it worse.

This has been discussed on many threads. Here is a recent one:
http://www.reefcentral.com/forums/sh...readid=1309598

You and two other people say they don't work. A majority of people here use them with very good results. Stop spreading misnforamtion based on your results and a few others. It's a small percent, that should not be taken as fact.

[Setec]

I think your math is wrong Jefe. If a pump will only move so much water and 45% of that water is going else where besides the main return, then yes, it is consumed. If I dump 1000 gallons of water into a garden hose and T if off at the end, 500 gallons will go left and 500 gallons will go right.

If I dump 2000 gallons an hour into my return system and 400 goes into my skimmer and 300 goes into my refugium that leaves me 1300 gallons to go back to my tank. After head loss or a control gate, I can have 1200 or less being dumped into my tank and fed back to the sump.

As for the bubble traps go, if they dont work then why do all of the top sump desinger/builders including Melev use them? I am not fighting you on this point, I just dont understand if they dont work then why do all sumps include them?

[Jefe12234]

Perhaps I'm misunderstanding your setup, but it seems to me like everything is located in your sump. If you have 2000gph entering your sump, then you will have 2000gph leaving the sump as well. All the water that passes through the filters still comes out in the sump and gets pumped back to the tank. Your garden hose analogy only works if the water is going to different places.

As for the bubble traps, I think they are just one of many examples of misinformation in the hobby. They look like they should work, so people assume they do. I will paste here what I wrote in the thread sjm817 linked to.

If you've ever watched microbubbles closely, they don't shoot to the surface like larger bubbles. They rise very slowly and are carried along with any current. The reason is because as the bubble size decreases, the volume decreases faster than the surface area. (This is the same reason that small grained sand provides such an immense surface area for a given volume). So the buoyant force becomes very small while the drag remains somewhat high. You just need a large volume and/or slow flow through the sump to allow enough dwell time for the bubbles to rise. A bubble trap actually forces the water to move through a smaller volume (the space between the baffles) which increases the velocity of the water and pulls microbubbles through.

I know a lot of people use bubble traps with success. I just think they would have equal or improved performance without them.

[mdelcomyn]

I think that both sides are right--baffles can work, but they certainly aren't a silver bullet for microbubbles.
If you have slow flow and some bubbles, baffles can help (some of) them get to the surface before the return pump.
On the other hand, if there is too much flow going through the sump three simple 1" spaced baffles just aren't going to cut it.
In my humble opinion, the trick is to have a slower rate of flow. I literally just set up my sump four days ago and I have no microbubbles. And guess how many baffles I have? Zero! I have only about 600 gph going through a 30 gal sump with a separate refugium tied in.
The bottom line is, they can work but don't always. No two set-ups are exactly alike, and what works for one might not for another. See what works for you!

[sjm817]

Originally posted by scotmc
You and two other people say they don't work. A majority of people here use them with very good results. Stop spreading misnforamtion based on your results and a few others. It's a small percent, that should not be taken as fact.

Its not misinformation, and there have been many people who say they dont work and also why. That is not the only thread on this subject. The reason they dont work is physics and has been posted more than once.

[hogben]

I like them farther apart so I can easily clean between/under them.

I also like a low flow (slow) sump they're quieter and no problems with bubbles.

You don't have to reduce your flow, but you can always just make the sump larger, it has the same effect.

[setec69]

[scotmc]

PLease give me some technical physics information on this, not your views.( ie something published) A properly set up baffle system will slow flow and allow bubbles to disappear. It's pretty simple.

[Setec]

My plan is to have 1 pump that T's off to 4 lines, 1 line goes to the tank ~ 1200 gallons, 1 line goes to my skimmer ~ 300-500 gallons, 1 line to my refugium ~300 gallons, and 1 line back to the sump to handle extra flow or to divert water away from the tank for feeding/water changes.

So the drains on the left of the sump are handling ~1200 gallons of water, the 2 drains in the middle are handling ~800 gallons and the pump is pulling ~2000 gallons.

Although, I just found out that I am calculating headloss incorrect. The pump assumes 1.5 inch all the way to the top of the tank. I do not have 1.5 inch pipe, my tank is drilled for 3/4 inch pipe, so that doubles the head loss on this pump. Assuming I run 1.5 to the bulk head in the bottom and 3/4 the rest of the way up, I am now looking at 10-12 feet of head loss brining this pump down to around 1600 gallons of pull.

As I still need the same amount of water feeding my skimmer, the tank will not have as much as I originally thought.

I may for the sake of argument not do an OUO trap, but still do an under over baffle before the return pump to keep turbulence from the drain section for affecting the water in the return section. I am thinking of a 3 inch spacing between the baffles.

[Jefe12234]

Originally posted by scotmc
PLease give me some technical physics information on this, not your views.( ie something published) A properly set up baffle system will slow flow and allow bubbles to disappear. It's pretty simple.

I don't think anyone has published data one way or the other on bubble trap performance. But a baffle system will increase, not decrease, flowrate. Instead of allowing the water to move through the entire cross section of the sump, a baffle blocks most of this cross section and forces the water through a much smaller cross section. It's like decreasing the diameter of a pipe; velocity increases. That said, I do think a single over baffle helps by bringing all the bubbles to the surface and reducing turbulence. Another under baffle, however, will just pull microbubbles down again.

[scotmc]

I hope Melev would comment on this. So far all I see is misinformation.

[mash2k]

I have never needed a bubble trap on any of my sumps. Never had a microbuble problem either. That said, that doesn't mean that the bubletraps don't help.

I have also used the filter socks to prevent microbubbles and they work great. The only thing I didn't like was that i had to switch them out every cou8ple of days to prevent a nitrate factory.

The sump that i am currently building has only 1 baffle. It has my skimmer then the next compartment has a benthic zone setup the way Mr Wilson described it.

We will see if I have a microbubble problem. I will report my findings soon.

[Jefe12234]

Setec, if your feeding your skimmer and refugium with separate lines then I assume they are in separate compartments within your sump. Is this right? If so, why not just run the drain line into the first compartment and allow each compartment to spill over into the next? Then you only need the tank return and a diverting valve on your return pump. It's a little hard to imagine your setup without a picture, but that is how most people do it. Also, the 3/4" plumbing is just another reason to use a smaller return pump; less waste due to head loss. I don't want to tell you what to do, it just seems like a waste and a potential problem using that pump the way you've planned.

[Setec]

They are in separate compartments in fact, the skimmer is external to the sump hence why I am using such a large pump. I was told the skimmer can take 700 gallons an hour easy, but I dont want to assume I will be pumping that much through it.

As for the refugium. I dont want all of my water passing through it. I like to be able to control the flow in the fuge. I will post a picture and see if that helps.

[seagirl]

Originally posted by scotmc
PLease give me some technical physics information on this, not your views.( ie something published) A properly set up baffle system will slow flow and allow bubbles to disappear. It's pretty simple.

This statement is incorrect. Jefe12234's analogy to the pipe diameter is correct, you have it backwards. I don't know why you keep saying there is "misinformation" in this thread, it seems you are the only one who doesn't understand it.

[scotmc]

Maybe your should try reading the entire thread. Or provide information on why baffles don't work. I guess all the people who use them are just seeing things and you three have it correct.