Water flow and calculations.

[MrDaytona]

I have 3 feeds that from my bottom drilled tank that have 1/2 inch elbows. I wish to use 3/4 inch pipe so I will use a 1/2 inch to 3/4 inch reducers and have all three feeds connected to one 3/4 inch output pipe that will feed my pump.
The pump will then feed my cannister filter and then return back into the tank. I will be using 3/4 inch pipe or flex hose thru out.

I must add three valves, one before the pump, one between the pump and filter, and one between the output of the filter and the feedback tube - they are needed to change the filter medium and/or change the pump.

Question: When I look at the 3/4 inch valves the valve portion necks the water flow down to 1/2 inch.
Is this detrimental to my water flow? If so my only alternative would be to use a 3/4 to 1 inch reducer and use the 1 inch valves.

One of my concerns is that the more connections you have the greater the chance of having a leak. Am I being overly cautious?

Thanks in advance for any replies.

 

[loganj]

Question: When I look at the 3/4 inch valves the valve portion necks the water flow down to 1/2 inch. Is this detrimental to my water flow? If so my only alternative would be to use a 3/4 to 1 inch reducer and use the 1 inch valves.

All valves will neck down some in the middle. I don't think this will cut your flow much as you already are limited to 1/2" fittings coming out of the tank. The only possible problem I can see is that you might get some cavitation due to the restrictions in the line. This will depend on the size of the pump. My guess is that, with three lines supplying the pump, it will be fine.

One of my concerns is that the more connections you have the greater the chance of having a leak. Am I being overly cautious?

As long as all the fittings are cleaned and properly glued, there isn't much chance of a leak. PVC glue melts the plastic together. JMHO.