Plumbing and return pump help

[Reef of Fillory]

I just plumbed my biocube 32 for a sump, and I am getting almost no flow from my quiet one 3000 pump.

I'm using 1" PVC to 1/2" vinyl tubing (for over stock biocube return outlet)

In order to equilibrate the return and the drain I have to almost entirely close the ball valve on the drain line. The flow is very very low, but the pump is rated for 725 gph so even with the reduction to 1/2" and the 90s I was expecting better flow.

Any suggestions? I'm looking for around 350-400gph flow through my sump

 

[jeff williams]

Increase the diameter or the hose to 3/4 or 1" on the return. By necking it down you create a lot more head pressure and the pump may not be rated for higher head pressure I'm not sure what its rating is but it should pump more volume at a lower psi with a larger pipe

 

[mcarroll]

I just plumbed my biocube 32 for a sump, and I am getting almost no flow from my quiet one 3000 pump.

I'm using 1" PVC to 1/2" vinyl tubing (for over stock biocube return outlet)

Any suggestions? I'm looking for around 350-400gph flow through my sump

In order to equilibrate the return and the drain I have to almost entirely close the ball valve on the drain line. The flow is very very low, but the pump is rated for 725 gph so even with the reduction to 1/2" and the 90s I was expecting better flow.

Expecting based on what? :)

The Quiet One 3000 appears to be rated for 758 GPH with nothing connected to it, and it has a 1" outlet that has been reduced to 1/2". Not ideal. ;)

Based on the flow curve, and assuming your return is about 4-5' over the sump, it looks like the most you could expect under ideal circumstances is about 500 GPH.

When I look at a friction loss calculator to see what effect the 3' of half-inch plumbing has, I get +1.5' of head pressure:

Pressure Loss (psi): 0.65 Head Loss (ft): 1.5
Line Number: .5" @ 3 feet length
Date: 10/12/2017
Nominal Pipe Size: 0.5
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.622
Fluid Velocity (ft/sec): 8.45
Reynolds Number: 41693
Flow Region: Turbulent
Friction Factor: 0.023
Overall K: 1.32
Piping Length (ft): 3​

The lower section of your plumbing appears to be mostly three-quarter inch or half-inch vinyl tubing. Assuming that's 3/4" tubing on the pump, and that's about two feet in length, it only adds +0.3' of head pressure:

Pressure Loss (psi): 0.11 Head Loss (ft): 0.3
Line Number: .75" @ 2 feet length
Date: 10/12/2017
Nominal Pipe Size: 0.75
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.824
Fluid Velocity (ft/sec): 4.82
Reynolds Number: 31472
Flow Region: Turbulent
Friction Factor: 0.024
Overall K: 0.69
Piping Length (ft): 2
​

The middle section with one-inch PVC for the elbows and reducer would look something like this, adding +0.7' of head pressure:

Pressure Loss (psi): 0.3 Head Loss (ft): 0.7​

Line Number: 1" @ 1 foot length
Date: 10/12/2017
Nominal Pipe Size: 0.75
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.824
Fluid Velocity (ft/sec): 4.82
Reynolds Number: 31472
Flow Region: Turbulent
Friction Factor: 0.024
Overall K: 1.9
Piping Length (ft): 1
Short Radius Elbows: 2
No. of Reducers: 1
Reducer Outlet Size (in) : 0.5


The total added friction loss from the plumbing would be something like +2.5'.

That takes your pumping height from 4-5' without friction loss.

Including friction losses, that pumping height goes up to 7-8'.

Referring back to the flow curve, you might only be able to get into the neighborhood of 250 GPH with this configuration.

What @jeff williams said. ;)

 

[Reef of Fillory]

Expecting based on what? :)

The Quiet One 3000 appears to be rated for 758 GPH with nothing connected to it, and it has a 1" outlet that has been reduced to 1/2". Not ideal. ;)

Based on the flow curve, and assuming your return is about 4-5' over the sump, it looks like the most you could expect under ideal circumstances is about 500 GPH.

When I look at a friction loss calculator to see what effect the 3' of half-inch plumbing has, I get +1.5' of head pressure:

Pressure Loss (psi): 0.65 Head Loss (ft): 1.5
Line Number: .5" @ 3 feet length
Date: 10/12/2017
Nominal Pipe Size: 0.5
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.622
Fluid Velocity (ft/sec): 8.45
Reynolds Number: 41693
Flow Region: Turbulent
Friction Factor: 0.023
Overall K: 1.32
Piping Length (ft): 3​

The lower section of your plumbing appears to be mostly three-quarter inch or half-inch vinyl tubing. Assuming that's 3/4" tubing on the pump, and that's about two feet in length, it only adds +0.3' of head pressure:

Pressure Loss (psi): 0.11 Head Loss (ft): 0.3
Line Number: .75" @ 2 feet length
Date: 10/12/2017
Nominal Pipe Size: 0.75
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.824
Fluid Velocity (ft/sec): 4.82
Reynolds Number: 31472
Flow Region: Turbulent
Friction Factor: 0.024
Overall K: 0.69
Piping Length (ft): 2
​

The middle section with one-inch PVC for the elbows and reducer would look something like this, adding +0.7' of head pressure:

Pressure Loss (psi): 0.3 Head Loss (ft): 0.7​

Line Number: 1" @ 1 foot length
Date: 10/12/2017
Nominal Pipe Size: 0.75
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.824
Fluid Velocity (ft/sec): 4.82
Reynolds Number: 31472
Flow Region: Turbulent
Friction Factor: 0.024
Overall K: 1.9
Piping Length (ft): 1
Short Radius Elbows: 2
No. of Reducers: 1
Reducer Outlet Size (in) : 0.5


The total added friction loss from the plumbing would be something like +2.5'.

That takes your pumping height from 4-5' without friction loss.

Including friction losses, that pumping height goes up to 7-8'.

Referring back to the flow curve, you might only be able to get into the neighborhood of 250 GPH with this configuration.

What @jeff williams said. ;)

Wow, thanks for all the effort!

The tubing coming off of the pump is 1" ID vinyl

I struggled to find a way to get what I needed in the space under the stand without blocking the skimmer cup. I have a couple of other pictures i'll post here in a minute.

I am not sure how to go about plumbing the return back in to the tank without going down to the 1/2" at the end [which fits the biocube outlet]. If going over the top of the back of the tank, do I just make a "U" with a 45 on the end with a piece of pvc shooting into the tank?

Or would a shorter run of the 1/2" make a difference for the flow? The flow is just trickling over the first baffle down in the sump.

Thanks again!

 

[Reef of Fillory]

How the 1" vinyl gets to the 1" PVC. I think I'll have to re do this whole section, thinking about putting a true Union ball valve up closer to the tank on the outside of the stand, have the vinyl come out to the back of the stand to a t with a Barb fitting with a valve for my reactor off of a 90

 

[jeff williams]

Just to add to what I posted earlier I use the same pump in my 60 gallon and I have it plumbed with a 3/4 or 1" return with about 4' of head and have a ton of flow also make sure the pump Inlet is open all the way

 

[mcarroll]

Consider just running vinyl or just running PVC. And yes, a couple of 90º's to get over the top is all it takes. You can get fancy and build a little spray bar or something, but maybe make that Phase II after it's working. :)

 

[Reef of Fillory]

Just to add to what I posted earlier I use the same pump in my 60 gallon and I have it plumbed with a 3/4 or 1" return with about 4' of head and have a ton of flow also make sure the pump Inlet is open all the way

I may just be a dummy, but I haven't noticed that there's an adjustable inlet? It's just a box with the output? I'll have to do some internet searching to see if/how to adjust the input because I didn't know it was adjustable!

 

[Reef of Fillory]

It it that ring on the front that is adjustable? Hopefully i've just got that closed off and all I really need to do is twist the pump open!

If that gets me to the flow rate I need, i'll forego changing my return plumbing. Don't want to re-buy pvc to get 40-50gph more, when I only really need 300gph [10x turnover for triton]

 

[Reef of Fillory]

Ran home on my lunch... The pump was closed almost all the way... Even with the 1/2" it has plenty of flow coming from/through the sump.

New problem now:

In order to balance the noise level from the drain, it lowers my return pump section too much. The drop from the skimmer section to the return pump section introduces bubbles which fill the tank when going through the return pump.

If I increase the drain flow, the return section water level increases, but the drain makes all kinds of noise.

Where my drain is currently puts me at my max sump level with return pump off, so I can't necessarily lower the drain pipe, or increase the water level in the return pump section [overflow during power off when drained back down]


I feel like the 1" drain lines are overkill for my tank/turnover because even with the pump opened up I have to have the ball valve fairly closed to make it quiet

Any more ideas? Thanks for all the help/suggestions so far!

 

[Fritzhamer]

That manifold of your is also creating the flow loss.

 

[Reef of Fillory]

That manifold of your is also creating the flow loss.

The flow is plenty now [for my needs] with the pump inlet opened up. Now i'm looking at a way to increase the return pump section height without adding more water.

I opened the pump inlet all the way [it must have been shipped all the way turned down]

I'm thinking that reducing the flow from the return pump might do the trick?
- Reduce return flow via the ball valve, or the inlet on the pump though?

 

[Reef of Fillory]

Here's the water level that gives no bubbles in the tank, but doesn't allow for the drain to siphon, which causes a lot of noise

 

[JoshH]

So you have a valve on the drain line correct?

 

[Reef of Fillory]

So you have a valve on the drain line correct?

Yeah I have a valve on the main [lower] drain, and a second drain as backup/trickle which does not have a valve. I also have a valve on the return line, but can't get the balance of

1) high enough water level in return pump section
2) drain line noise level
3) Power off sump water level

 

[JoshH]

So ideally, you're return pump section will drop in water height until your system is entirely full (all your plumbing return and manifold wise). After your pump has filled this it Will stop dropping in the return section, At this point you want to add water until your pump is no longer sucking air in creating the bubbles in your display. Personally I would raise your main siphon pipe to within 2 inches of your secondary drain. Right now the way you have it set up it will pretty much drain most of the water in your rear chamber into your sump causing your water height issue. Also tune your main drain pipe to a full siphon with a little trickle flowing over your secondary drain. This should fix your noise issue, your 1" drains are a good size for your tank, I have a 1" BA set up on my RSM C130 and it's dead silent, yours should be the same.

 

[Reef of Fillory]

So ideally, you're return pump section will drop in water height until your system is entirely full (all your plumbing return and manifold wise). After your pump has filled this it Will stop dropping in the return section, At this point you want to add water until your pump is no longer sucking air in creating the bubbles in your display. Personally I would raise your main siphon pipe to within 2 inches of your secondary drain. Right now the way you have it set up it will pretty much drain most of the water in your rear chamber into your sump causing your water height issue. Also tune your main drain pipe to a full siphon with a little trickle flowing over your secondary drain. This should fix your noise issue, your 1" drains are a good size for your tank, I have a 1" BA set up on my RSM C130 and it's dead silent, yours should be the same.

Turning the main drain to a siphon involves closing the ball valve until all air is purged from the line right?

I thought that with the primary and secondary line that close to each other that a vortex would be created on the main drain and a siphon wouldn't be allowed to start?

I set up a beananimal drain on my 75G and it was easy to adjust it, but I can't quite get this setup working. If I take PVC over the back of the biocube, I might be able to allow less to siphon from the main tank to the sump which would allow me to increase the sump water level in the pump section.

Right now I can't add any water to the sump due to power off water level issues. I am assuming that raising my primary drain line would do the same [allowing more water to be added]?

Thanks again All!

 

[JoshH]

You're correct, basically you're wanting to turn the valve to the point the primary is no longer sucking air in possibly even further than that to match the flow of your return pump. My secondary and primary drains are only 1" in height difference however they have a U shaped design on the top of each pipe. I don't see a vortex being created by being so close in height but I could be wrong. You're basically creating a BA set up without the extra emergency drain or herbie set up I believe. And theoretically raising the primary drain might help with the water height issue in the sump. Another possibility is your sump in general is just too small to handle the back flow of your system which would be the worst case scenario.

 

[Reef of Fillory]

You're correct, basically you're wanting to turn the valve to the point the primary is no longer sucking air in possibly even further than that to match the flow of your return pump. My secondary and primary drains are only 1" in height difference however they have a U shaped design on the top of each pipe. I don't see a vortex being created by being so close in height but I could be wrong. You're basically creating a BA set up without the extra emergency drain or herbie set up I believe. And theoretically raising the primary drain might help with the water height issue in the sump. Another possibility is your sump in general is just too small to handle the back flow of your system which would be the worst case scenario.

I was hoping that me making the baffles too high wasn't the case, as I don't want to take apart the sump now after drilling and plumbing the display tank.

What advantage is there to using a "U" on the inlet like the BA system uses compared to just a straight standpipe? I had the upside down "U" on my 75g but I did that mostly so that snails and fish couldn't get in to the pipes.

The T in the BA siphon tube [sealed?] allows air to collect at the top of the capped T outlet, is this an intended design that you know of? With the siphon starting and stopping, wouldn't the air in the top of that T, without an outlet inhibit a siphon from restarting? Or does that pocket just stay where it is?

Like I said, it worked for me on the 75G even though I didn't understand what I was doing, I just followed directions

 

[mcarroll]

Any more ideas? Thanks for all the help/suggestions so far!

This mod does add a lot of complexity where a simple BioCube works pretty well "out of the box".

Without knowing what you're up to/why you're doing the mod I have no ideas – other than slowing the pump down to what the tank and drain were made for. Probably only 100-200 GPH for such a small tank volume. Which is fine! :)

While that makes for a perfect fix, I suspect it may also defeat the point of what you're doing. Since there's nothing really wrong with 100-200 GPH, maybe the "real problem" is that your pump is too big?