FragMaster":1qyipiez said:
THats why you use a ball valve on the return side to make sure you dont run dry or low.
That way you can adjust it to a lower return rate if the pump is to strong, or simply buy a more powerfull pump if the rate is too Slow, and adjust or fine tune it with the ball valve.
I'm not really sure what you're trying to get at here. There's no need to restrict the intake of the return pump and it's definitely not good practice as it can cause cavitation.
At any rate, in this case you can't really use a valve to raise the water level in the display tank much. You could restrict the drain lines with valves, but all that will do is raise the water inside the overflow boxes. It won't effect the level in the main tank much unless you restrict the drains so severly that the water level backs up above the overflow boxes which pretty much defeats the purpose of an overflow box. :wink:
To me it makes more sense to do a little math first and get an idea of what you're dealing with so you can minimize the chances of having to change stuff later like box height, plumbing and pumps. That's all we're really doing here...
FragMaster":1qyipiez said:
What we should also be asking is what size is his pump. What size tube is he using, how many 90/45 deg angles as well as how many vertical and horizontal feet of return piping will there be.
Yes, that information would be needed to estimate the flowrate, and as we mentioned earlier in the thread, flowrate will play a role in what the running water level is in the display tank.
FragMaster":1qyipiez said:
If your pump is too strong you can also restrict the flow by simply adding a second return point.
Which is IMHO the prefferd method for more water movement.
Actually adding another discharge point will decrease the amount of restriction on the pump resulting in more flow, not less. It will decrease
velocity at each outlet, but will result in a slight increase in overall flow volume.