Question regarding Calfo Manifold and RC Head Loss Calculator

[nekomi]

Hi everyone,

I'm currently in the process of planning a Calfo-style closed-loop manifold for my 37gal Oceanic cube. When I originally designed the system over a year ago, I didn't understand much about plumbing, and ended up buying the wrong pumps.

With room for only a 10gal sump, my return pump (submerged Quiet One 3000) is moving water way too quickly through the sump and creating tons of microbubbles, not to mention that I hardly get anything out of my skimmer. Even then, I'm still only getting 15x flow in the display, due to head loss. And I can't go any larger due to the afore-mentioned issues. :(

So, I want to downgrade my sump return to a much quieter pump (hopefully solving my minimal skimmer output and microbubbles), and "pick up the slack" with a Calfo closed loop manifold. But I'm having trouble figuring out what sized pump I need.

The tank measures 24" long x 18" wide. I'm going to mount the CLM pump on a shelf, so I figure I'll have about 18" of head loss before the water enters the actual perimeter manifold. The loop itself constitutes 7 feet (seriously!?) of horizontal pipe... I'd like to put 2 tees on each side of the tank for a total of 8 tees.

As for pipe diameter, I'm unsure of whether to use 1" or 3/4" diameter pipe for the manifold, and also whether or not I should reduce the size for the actual tees.

As for the RC calculator, when I put all these values in (I used the Quiet One 3000 in my calculations just to see if it would work), the computer spit out a flow rate of 569 gph. Is this the total GPH coming out of ALL the tees (i.e., I should divide it by 8 to get the total coming from each tee), or does this number represent the flow coming from each individual tee?

Thanks for any help... I am thoroughly confused, even after reading numerous threads on this subject. Plumbing was never my strong point. :D

[Keelay]

The RC calculator won't acurately model your setup. It sounds like you split your outlets and then go parallel. The RC calculator will not account for this. This will count in your favor since you are effectively reducing the head here. How much? You're going to have to guess.

Another thing. to calculate the hieght part of the head, don't consider where the pump is. Consider only the difference in inlet to outlet, the number of different junctions, and the length of the pipe.

On another note. Last night, I was plumbing a skimmer drain to another compartment in my sump. I needed to turn a pipe 90 degress so I used an 90 elbow. My skimmer water level jumped 1". That was unacceptable (based on what I was trying to do) So I removed the 90 and added two 45's instead. The water level didn't even move up this time. The only difference was the tight turn vs slow turn.