Feed pump, external skimmer and back pressure question

[phillygeeks]

I have an MRC Pro-1 external skimmer. The recommended feed rate is 300-500 gph. However, in the installation instructions it recommends installing above the sump to decrease back pressure. I will have it mounted on the floor at the same height as the sump, as seen below. My question is would the back pressure affect calculating the power of the pump needed much like head pressure of the plumbing? If so is it a similar calculation to head pressure in terms of distance traveled and elbows, etc.? ... oriIs back pressure just something that will make the skimmer less effective and don't take it into consideration when choosing a feed pump?

 

[MnFish1]

Not sure how to calculate all of that without the dimensions, etc about what pump, etc you're planning to use. But - many times - the issue is not the 'back pressure' - as much as the fact that back pressure causes the skimmer to continuously overflow (i.e. its beyond the ability of adjustment). The best solution is to raise the skimmer up - I have to raise mine about 6 inches. If I do not - it just constantly overflows. hope this helps.

 

[phillygeeks]

Not sure how to calculate all of that without the dimensions, etc about what pump, etc you're planning to use. But - many times - the issue is not the 'back pressure' - as much as the fact that back pressure causes the skimmer to continuously overflow (i.e. its beyond the ability of adjustment). The best solution is to raise the skimmer up - I have to raise mine about 6 inches. If I do not - it just constantly overflows. hope this helps.

Thanks. I think I can get a rough calculation on head pressure on my own. I was curious if all the back pressure and plumbing with return to the sump would affect the feed pump power necessary to achieve the goal "feed rate" of the external skimmer so I can take that into consideration along with head pressure in choosing a feed pump.

I have had that issue with my internal skimmer. That is a lot easier to adjust. I guess I have seen a number of setups with external skimmers sitting at the same level as the sump and the plumbing that came with the skimmer was designed to fit specifically with the return to the sump as is seen below

 

[MnFish1]

Thanks. I think I can get a rough calculation on head pressure on my own. I was curious if all the back pressure and plumbing with return to the sump would affect the feed pump power necessary to achieve the goal "feed rate" of the external skimmer so I can take that into consideration along with head pressure in choosing a feed pump.

I have had that issue with my internal skimmer. That is a lot easier to adjust. I guess I have seen a number of setups with external skimmers sitting at the same level as the sump and the plumbing that came with the skimmer was designed to fit specifically with the return to the sump as is seen below

BTW - admittedly - I have not researched this skimmer - BUT - My guess is it doesn't have to be above the sump - just above the water level of the sump - or near that. Hope it works out - nice set up - is your tank - upstairs - or was that original picture the 'layout'. Cause this one looks different

 

[phillygeeks]

BTW - admittedly - I have not researched this skimmer - BUT - My guess is it doesn't have to be above the sump - just above the water level of the sump - or near that. Hope it works out - nice set up - is your tank - upstairs - or was that original picture the 'layout'. Cause this one looks different

Thanks! My gut is telling me to go with an adjustable DC pump for now like the Sicce Syncra SDC and just figure it out from there.

The 2 pics in this thread are just from different angles. The standpipe is hiding in the first pic. I am working on getting all the plumbing done. Very painful!

I have a few pics in my build thread showing the DT. It's in an adjacent room on the same level approximately 6 feet away

 

[MnFish1]

Thanks! My gut is telling me to go with an adjustable DC pump for now like the Sicce Syncra SDC and just figure it out from there.

The 2 pics in this thread are just from different angles. The standpipe is hiding in the first pic. I am working on getting all the plumbing done. Very painful!

I have a few pics in my build thread showing the DT. It's in an adjacent room on the same level approximately 6 feet away

I would not overcomplicate it. Use the directions from the skimmer you bought. If they say above the sump - do it above. You're trying to rig it so it will work - you will lose electrictrical efficiency - and potentially other issues. - just follow the directions. I know you have the plumbing already done - re-do it. Raise the skimmer. JMO.

 

[phillygeeks]

I would not overcomplicate it. Use the directions from the skimmer you bought. If they say above the sump - do it above. You're trying to rig it so it will work - you will lose electrictrical efficiency - and potentially other issues. - just follow the directions. I know you have the plumbing already done - re-do it. Raise the skimmer. JMO.

The sump was a custom build from MRC. They sent the plumbing you see to work with this specific skimmer and sump set up. I haven't done any modifying on that part of the plumbing myself. I assume it will work given that was how they designed it. However, in the actual skimmer directions, if you were to buy it off the shelf, it makes a recommendation to have it above the sump. It certainly wasn't worded as a necessity.

 

[MnFish1]

The sump was a custom build from MRC. They sent the plumbing you see to work with this specific skimmer and sump set up. I haven't done any modifying on that part of the plumbing myself. I assume it will work given that was how they designed it. However, in the actual skimmer directions, if you were to buy it off the shelf, it makes a recommendation to have it above the sump. It certainly wasn't worded as a necessity.

OHHHHHHHH - all good - then in that case - I would go back to MRC and say 'what the heck' - the instructions say this and you've given me that.