water movement

[carpenterwrasse]

here's the question for years i have not used any special formula to figure water movement in my tank but I want to learn...I want to employ a clm on my 75 gal tank 1 on the top and one in the bottom buried in the sand bed. I am not familar with head pressure and friction loss. my tank has 2 holes drilled in the back with bulkheads for exiting water they are 3/4, they lead into a t to form a single line into my sump.. I have a rio 2300 as a return pump...I have to adjust the valves to have a good in flow to a good return flow. question... If i make it 2 lines into the sump will i have more water leaveing to tank...i have valves in the lines coming into the sump as well as the return that i have to consistanly have to tweek. If i make it 2 lines into the sump will i have to have 2 valves to regulate the water coming in? and should i increse the size of the return pump.... I plan on a total tear down with a refit for all pvc or should i go with a pvc tube combo. people help me to finilize this rebuild

[hummer]

why do you have to tweek the valves whats the tank doing?

[Iconz]

well, i've done alot of reading on this subject lately bud, and here's what I've learned...

I'm assuming you either have an overflow box or a built-in overflow.

- Valves on an overflow line can cause some serious noise issues.

- 3/4" pipe is going to give you a MAX of 500gph. This is due to friction and just size limitations.
- So, yeah, 2 x 3/4 will give you a max of 1000gph.

- Flex pipe will help you minimize friction/resistance. Especially if your drain pipes don't go STRAIGT DOWN into the sump. I say this because if they don't, you'll have to use some sort of angled connection 90 or 45 degrees... this would hurt your flow ALOT more than a flex pipe bent over a much longer distance.

Return Pump
The ideal thing is to have your return pump = to your overflow rate... your MAX is 1000gph. And pending your return head height... (We'll say 5' for calculations)

For instance, a quiet one 5000 (rated at 1330gph at 0' head) would give you 800gph with 5' of head, 1 90degree elbow and 1 45 elbow.

Head loss calc. (http://reefcentral.com/calc/hlc2.php?submitted=1&VerticalLength=5&HorizontalLength=0&PipeDiameter=1&PumpID=125&Elbows90=1&Elbows45=1&GateValves=0&BallValves=0&Couplings=0&CheckValves=0&Exits=1&Entrances=1)

CLM

For the CLM, you won't have any head loss. It will at least be negligable (sp?)...

- What you do want is 3-5x turnover / hour per outlet
- You'll want to have 4-5 outlets per long side and 1 or 2 per short side... Keep in mind you can close some of these off if you need to, but its ALOT better to have more than to not have enough!
- So, for a single outlet with 75 gal's at 4x turnover / hour.. that's 300gph X 10 outlets... 3000gph pump.... Something out of the sequence line should do you real well here. Probably a Dart.

This is just some info for ya, if ya got any questions.. fire away! Just tryin to return some of the help i've gotten from you all!

Keep me/us posted!

[carpenterwrasse]

i tweek the valves to try and equalize the out to the in

[carpenterwrasse]

iconz its something i will be looking into