Intake plumbing redo

[Gerryd]

Hi all,

I am using the following INTAKE config on my 180:

Current setup is 2 X 1" drilled input bulkheads (one on each end of the tank) that are connected via 1" spa flex to a SINGLE 1" T that couples up to the 2" pump intake via 1" flex hose. So really restricting the input flow here and not really getting the benefit of the dual intakes. Stupid I know.

Option 1 would be to connect EACH of the 1" bulkhead intakes to a SINGLE length of 2" PVC pipe that connects directly to the 2" pump intake. Not sure why I did not do that originally. I am thinking this should improve the intake flow by at least 25%(???) and will thus improve outlet flow as well. I know I am causing the pump to underperform as it is setup now.

Option 2 would be to install one of the CPR overflows in addition to option 1 and also connect that to the 2" PVC. That would provide 3 inlets and possibly 4 if I got the largest CPR model with the twin intakes (sweet). 1200 gph for the twin intake model.

The blackfin pump has a 2" inlet and outlet. It flows 3600 gph so I am pretty sure it can handle the extra input with no issues even if I add the overflow...I have it throttled back anyway.

Option 2 will provide some additional flow as well. Just not sure I want to be concerned with the occasional loss of the siphon.

I currently have a closed loop canister system. I think even option 1 will improve things considerably.

Am I on the right track or am I just up too late?

Appreciate any comments.

 

[shoggoth43]

1" pipe is .785 sq " cross section

2" pipe is ~3.14 sq " cross section

Right now you have .785 sq", plus head pressure from both streams crashing into each other and then making a right turn into the pipe inlet.

Option 1 will get you to 1/2 of the 2" pipe's cross sectional area. If you use something like a squid ( 4 or 5 1" inputs to a 2" pipe ) then you've doubled your area and I would expect flow to roughly double instead of just a 25% increase as long as you don't do any right angle bends in there like you have with the T fitting.

Option 2 could theoretically give you full flow in the system with a squid, but if you EVER lose siphon ( unlikely with that kind of flow ) you're in for a world of hurt. This ALSO assumes that you run some kind of herbie setup, or something that otherwise gets rid of the air, so that you don't have a lot of air injected into your pump intake from the water crashing down the overflows. Using a durso standpipe or similar will inject massive amounts of air. This will cause you some grief in the pump.

Other ideas:

Option 3. Add another bulkhead? 1.5" maybe? That's 1.75 sq" cross section. Plumb that in and you've exceeded the pumps intake cross section. < - good thing.

Option 4. Alternately, skip the overflow. If you have bulkheads already, just run one or two complete siphon tubes over the side and skip the overflow idea. No air to suck in. The predrilled bulkheads seem to indicate you're using closed loop anyway so no risk of flooding. With that kind of flow any siphon breakl/leak is likely to just suck the air along into the pump and be expelled so the two overhanging siphons might even be self priming as long as their intakes stay underwater. Since it isn't a constant massive injection of air you will likely be fine. You could just do the 1.5" over the top siphon tube either with your 1" pipes or run 2 of them and just use your existing bulkheads for a different loop. The white PVC could be painted, or possibly dyed black and you won't see it.

Option 6. Run a 2" siphon tube over the side and be done with it and use the 1" bulkheads for something else.

Option 7+. Stuff we haven't even thought of yet.

Hopefully that can give you some ideas.

-
S

 

[Gerryd]

S,

Many thanks for the multiple options

1" pipe is .785 sq " cross section

2" pipe is ~3.14 sq " cross section

Right now you have .785 sq", plus head pressure from both streams crashing into each other and then making a right turn into the pipe inlet.

Yes, but it is a DOWNWARD right turn lol

Understood that this is FAR from optimal and bordering on idiotic... Not sure what I was thinking about when I did this, probably getting it done if I remember I know these things about pipe diameter and flow rates, friction, etc but did not apply them....doh!

Option 3: would be out simply as I do not want to drain/drill the tank.

Option 4 and 6: I will respond later. I like this idea but have some questions....

Option 7: I have a mix of all option running through my head now lol

However, to get the most/quickest bang for my buck, or the low hanging fruit as they say in the biz lol I will do the following:

Option 1.

The pump inlet will have a 12-18" section of 2" PVC. Spaced every 3-6" there will be a 2" T and at the end a 2" 45 or 90 elbow. These will be the INTAKE ports into the main intake section of 2" pvc. I thought the spacing of the ports would help a bit with the merge of mutliple flows.

I will create 4 intake ports (3 T and the elbow) and will cap TWO of them while I toy with the other siphon/overflow options. These can then be used for up to a 2" intake later on Can be easily hooked up later.

Each of the remaining intake ports will be connected to a 1" intake. Each inlet will also have small 2-3" section of 2" PVC pipe so that the 1" flow increases to 2" PRIOR to hitting the main intake pipe section.

Each intake will be fitted with a ball valve to control/shut off flow. I am thinking that change alone will double my intake flow and provide for some future flexibility.

On the output side, I will change to use a cone distributor like the 2" to 5x1" model found here:

http://www.flexpvc.com/cart/agora.cgi?cart_id=3501255.22966*6p7yV0&product=PVC-Distributors

This is a great thread where some nice plumbing was discussed for a 150 by Jdowns...

http://www.barrreport.com/showthrea...wners-and-Reeflo-Pumps-FYI?highlight=blackfin

Outlet enhancement:

Currently I am sending the 2" outlet from the pump to a SINGLE 1" flex hose that has 2x1" T and a 1" elbow to drive my 3 parallel legs. Again not optimal but again all this has to fit under the tank.

The distributor should more evenly flow the water to the various legs and cause less friction and flow loss. I will cap or create a bypass with the extra outlets on the cone. The cone will fit directly to the 2" outlet pipe so each leg should get MUCH better flow than they are now.

Once the parts are in, should only be a few hours of work.

I think these enhancements will get me a nice improvement of flow for a few $ and some time and planning.

At least I am learning now before I do my new tank LOL

Thanks again for the help!

 

[shoggoth43]

How's it coming? What did you decide on?

-
S

 

[Gerryd]

See latest reply I JUST posted this second.

http://www.barrreport.com/showthread.php/5408-Large-Tank-Owners-and-Reeflo-Pumps-FYI?p=46863

BTW, how would you just plumb a siphon and no overflow? How do you start the siphon? I see it but don't if you know what I mean.

Thanks again!

 

[shoggoth43]

The siphon would just be a tube from your 2" to 5 way 1" cone or some other fitting arrangement going over the top of the tank in the usual U shape.

To start it there's two ways I can think of leading to a third idea.

One would be to stuff a bit of airline into the tube up to the top and then suck out the air to get it going, this sometimes imparts a bad taste directly on your tongue.

Another method was to have a way to pour water into it but this requires extra fittings and may allow air leaks in. The air leaks. if small enough, might not be a big deal since the tiny bubbles would just get dragged on through the pump so you probably wouldn't break the siphon since the bubbles couldn't build up.

I was kind of banking on this idea as a third method. If you look at how the hang on back filters work, with a little water in the impeller chamber it slowly sucks out air in little spurts and draws the water up the tube as it gets rid of the air. In your case I was figuring that since you'd have the two direct feeds from the bulkheads you'd have a flooded pump so those feeds would work no matter what. After that, the other feed into the pump, the over the top feed, would have the air drawn out by venturi action from the other two feeds in the cone fitting and slowly purge the air out. Eventually you'd get enough air out of the tube like the HOB filters and then whoosh, the siphon would start. You'd have bubbles everywhere for a few minutes but at that point you're primed and good to go. If the intake is low enough in the tank you may never lose prime. But if I'm right, you'd have a self priming siphon anyway so it wouldn't be that big a deal if you did. Sadly the only way I can think of to prove it would be to actually try it, but if you're going to cap off those inlets anyway it should hopefully be easy enough to try and cost very little. Putting your hand over the inlet should prove if it's working, or the large tornado in the tank from all the extra flow might prove it as well.

-
S