System Flow Rate

[kiwis]

I have a 140L system (120L display tank & 20L sump) and a Moray 2300 return pump.

That return pump is rated as 2,200 liters per hour and max height 2.2m

http://www.aquaone.com.au/prodinfo-aquaone/MorayPumps.pdf

I've put a plastic ball valve on the return line to slow it down in an attempt to make my system quieter, I've got this set to between 40-50%. Will this slow the rate of the filtration too much for marine?

Thoughts?

Even if it's pumping 700L an hour the system (1/3 the pumps capacity) it's still turning over 6 times an hour..

 

[Mark Bianco]

IMHO. 6 times an hour is plenty for turnover to your sump and tank. Where it ay get a little sticky is if you have corals that require super really high flow that can be remedied by adding a powerhead. The other issue if at the lower flow if you have any dead spots in the tank. If you do the try moving the return/s to a different spot, if that doesn't work once again a inexpensive small powerhead or two will do the trick..

Mark

 

[Daniel Waters]

Will this slow the rate of the filtration too much for marine?

it's still turning over 6 times an hour..

A 6x tank turnover is fine for filtration purposes, unless you're running something like triton, which I think recommends a 10x turnover. In my opinion, tank turnover per hour is not nearly as important as internal flow within the tank. For instance, I probably only have 5x turnover through my sump but probably 50x turnover inside my tank through the use of additional powerheads. A 5x turnover inside my tank would not be nearly adequate flow for my acropora. Obviously you should gauge your livestock, corals, and so forth to determine what type of internal flow you need. But as far as filtration, I personally wouldn't even worry about tank turnover unless it was less than 4x an hour (and even then I'm not sure I'd worry about). Less turnover through the sump just means greater contact / dwell time (in my mind), so I'm not sure if decreased tank turnover would negatively impact filtration capability or not. Of course, if you're using filter socks or carbon, increasing your tank turnovers will result in more mechanical filtration of this type.

 

[kiwis]

Thanks, I was looking at getting a power head to tackle that part.

 

[Engloid]

Unless you have a huge tank, you don't need anywhere near that turnover in the sump. Even if you had about 50gph, you'd likely never be able to test any difference in the chemistry of the sump water vs the tank water. I would not advise any valves in the drain unless you have a three drain setup, including an emergency drain. Trying to tune a valve to your exact flow rate is not easy to begin with, but it can be something simple like an air bubble, a snail, slime buildup that changes the amount of flow through the valve and causes your tank to overflow.