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
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.
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!