There's got to be a Mech. Engineer somewhere here that can explain why you don't need ball valves on a closed system like a Calfo Manifold...

OK here is my theory, you shoot water through the pipes so fast that only some gets split off to any given tee. The rest of it is propelled super fast on to the next tee because it doesn't have time to make turns at the tee. However at the end tee either there is just the right amount of water that comes out or you could launch mysis from it at the speed of light!

:mrgreen:

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I'm not an engineer but here's what I figured. If you have a 1" return but only use 3/4" output holes, it will create back pressure on the main line. This, in theory, should pressure up the main line enough to have even flow out of all holes. Kind of like those long irragtion hoses with all of the tiny holes in them. A pressure rated pump will keep the line pressured better than a none-pressure rated pump.

Pasca'ls Law ? I thinkthe water will basically be pushed throughoout the system at the same preasuure (assumong the outlets are basically at the same hieight).

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Catherine, don't get me wrong about the pump thing. Any pump will do the trick but pressure rated pumps won't have the head loss.

I'm thinking I'll be going with the Reeflo Snapper pump. I chose it mostly for wattage (I'm on a power budget), and it has the highest head at 0ft. I can't remember if its pressure rated or not.

Thoughts on my pump choice?

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See, that's the thing that is dependant on many other variables. You need to decide how many output nozzles you will have first, as well as the diameter of each nozzle. If you used a Mak4 that puts out roughly 1200 GPH though a 1" return line, and you 6 nozzles should get 200 GPH per nozzle. If you reduce your nozzle diamter to 3/4" then you effectively have more force of water pressure coming out of each nozzle, but still maintain about 200 GPH out of each. This would change your flow style though, much like the difference between a maxi-jet and a koralia.

As with so many things in this hobby, I would buy a bigger pump than you might need. It saves you from having to upgrade later.

I should have elaborated, my bad! :redface:

Okay so I've figured that I will probably be doing 2 x 2" drains in a single overflow box. The overflow box will be mounted exterior to the tank itself, and will probably only be about 7"-8" if I can get away with it. I'm still researching this.

For returns on the calfo manifold I was thinking of doing 9 returns. I am still debating doing two additional returns in the center of the tank, directly through the back glass; one below the shallow overflow box, and possibly one within it. I am pretty sure I'll be doing the manifold with 1" pipe and loc-line.

I did choose the snapper because of its high flow rate, higher then I suspect I need. I figured I would need minimum 1000gph at 0 head. Since the snapper can be throttled back, as well as its low power draw, I think this is the pump for me.

Does that clarify where I'm trying to go with this? Anymore thoughts on my pump selection?

Catherin, look here and tell me what you think (scroll down to pictures and read his explanation). Wonder if that's a good option?

I'm assuming your taking about the guy's DIY coast to coast overflow? Well it looks pretty functional for starters. It seems to provide great surface agitation, and I would assume good internal flow as well.

Since it seems that it would work on a smaller system, and provide good flow, it probably would work. I would just have then focus on making it a little prettier.

Thanks!