Manifold pressure problem

mark freshwater · Oct 5, 2018

Hi,
I have some rowaphos in a fluid bed filter , i used to have it hanging on my tank running off a 2500lph powerhead.
There was more than enough flow and i had to put a tap in to turn it down a bit.
I have now added a sump and it now runs off 1 of 4 outlets on my manifold , but it seems that it has to much back pressure in the bed filter and hardly any water flows thru it.
if i turn all the other taps off on the manifold it doesnt help as more water just goes up the main return.
i could close the return tap off more but then i am restricting water to the DT and also it wouldnt be good for the pump.
There is a ball in the the bed filter i imagine to stop it draining in a power outage or stopping the media from being siphoned into the tank , if i remove this ball would it help or has it got to be left in there ?.
Or can anyone think of how i could get it running better.

The pipe 2nd from the left is the bed filter , u can see its only trickling

bed filter with rowaphos

Return tap already closed a bit

Crabs McJones · Oct 5, 2018

What size return pump are you using? My guess would be you need to go bigger so that you can A: provide your display with the amount of flow you want and B: have enough pressure to feed your manifold. If you go with a bigger pump you can throttle it back with the ball valve to the display and that extra pressure would be applied to your manifold, and then each valve on there would dial back to run your equipment :)

mark freshwater · Oct 6, 2018

Hi,
My pump is 4400 lph , my tank total volume with sump is 340 litres , and my overflow hang on box is rated to 2500 lph.
I could as you said throttle it back , because there is plenty of flow to the tank , my main concern is that i will be trying to put alot of flow thru the smaller manifold outlets and will break the pump.
I have a spare outlet off manifold running nothing and also a 2nd spare outlet just for water changes that i could open if needed. ( the other 2 go to fluid bed and uv)
If i shouldnt worry so much about stuffing the pump, would i just close the ball valve on the return until i get the desired flow to the manifold?

mark freshwater · Oct 6, 2018

Crabs McJones · Oct 6, 2018

mark freshwater said:
Hi,
My pump is 4400 lph , my tank total volume with sump is 340 litres , and my overflow hang on box is rated to 2500 lph.
I could as you said throttle it back , because there is plenty of flow to the tank , my main concern is that i will be trying to put alot of flow thru the smaller manifold outlets and will break the pump.
I have a spare outlet off manifold running nothing and also a 2nd spare outlet just for water changes that i could open if needed. ( the other 2 go to fluid bed and uv)
If i shouldnt worry so much about stuffing the pump, would i just close the ball valve on the return until i get the desired flow to the manifold?

I would try that and see how it works, most pumps are adjustable, so creating artificial head pressure on them shouldn't harm anything. Dont get me wrong you dont want to completely block it off, but with the return and then the manifold you should be ok :)