Return pipe size question.

azsoccerpop · 07/04/2018, 03:42 PM

I have a 150 gallon that is already drilled and fitted with 2x 3/4" bulkheads for the returns. I am going to use them. Right now I have 1 Varios 6 pump and was thinking of adding a second so that I have 1 for each return. Because I have to scale down to a 90 degree 3/4" elbow into the bulkhead, does it make a difference if I run 1-1/4" pipe over 1" pipe as far as I can go. Or will the 3/4" bulkhead reduce the flow to similar GPH regardless of the diameter of the pipe used up to that point? Much of what have I read shows almost a double of the capable GPH for 1-1/4" over 1"

Vinny Kreyling · 07/04/2018, 05:13 PM

Try to run the size of the pump outlet as far as you can before reducing it.
2 pumps could be pushing it.

mfinn · 07/04/2018, 05:55 PM

I wouldn't add a second pump.
A single VarioS-6 is more than enough for a 150 gallon tank.

azsoccerpop · 07/04/2018, 09:20 PM

I have the 6 currently on my 90 gallon and maxed out it is pushing 400 gph based on apex 1" FMM feedback I know it is rated at 1500+ GPH but there is no way it is running that much and the 90 has had issues some of which I think is based on turnover. One of the returns on the new tank will go right back the other will be feeding a 3 port manifold then on to the tank and I am hoping for close to 900 gph turnover from FMM

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mfinn · 07/05/2018, 08:06 PM

Instead of looking to add a second pump I would look into why a pump that's rated at 1720 gph at 0 head is only getting 400 gph on your 90.
According to the manufactures specs the 400 gph figure would be at almost 11.5 feet of head pressure.

07/04/2018, 03:42 PM	#1
azsoccerpop Registered Member Join Date: Oct 2016 Location: Gilbert, Az Posts: 232	Return pipe size question. I have a 150 gallon that is already drilled and fitted with 2x 3/4" bulkheads for the returns. I am going to use them. Right now I have 1 Varios 6 pump and was thinking of adding a second so that I have 1 for each return. Because I have to scale down to a 90 degree 3/4" elbow into the bulkhead, does it make a difference if I run 1-1/4" pipe over 1" pipe as far as I can go. Or will the 3/4" bulkhead reduce the flow to similar GPH regardless of the diameter of the pipe used up to that point? Much of what have I read shows almost a double of the capable GPH for 1-1/4" over 1"

07/04/2018, 05:13 PM	#2
Vinny Kreyling Registered Member Join Date: Nov 2002 Location: Miller Place, NY Posts: 7,206	Try to run the size of the pump outlet as far as you can before reducing it. 2 pumps could be pushing it. __________________ 250 gallon mixed reef, 2 Reefbreeder's Photon V 2, Deepwater BLDC 12, DAS EX-3 Skimmer, MTC mini cal, 2-3/4" Sea Swirls, Aquacontroller & 6 Tunze pumps.

07/04/2018, 05:55 PM	#3
mfinn Registered Member Join Date: Apr 2002 Location: Olympia. WA. Posts: 8,648	I wouldn't add a second pump. A single VarioS-6 is more than enough for a 150 gallon tank. __________________ 240 gallon soft coral tank 50 gallon lps tank

07/04/2018, 09:20 PM	#4
azsoccerpop Registered Member Join Date: Oct 2016 Location: Gilbert, Az Posts: 232	Return pipe size question. I have the 6 currently on my 90 gallon and maxed out it is pushing 400 gph based on apex 1" FMM feedback I know it is rated at 1500+ GPH but there is no way it is running that much and the 90 has had issues some of which I think is based on turnover. One of the returns on the new tank will go right back the other will be feeding a 3 port manifold then on to the tank and I am hoping for close to 900 gph turnover from FMM Sent from my iPhone using Tapatalk

07/05/2018, 08:06 PM	#5
mfinn Registered Member Join Date: Apr 2002 Location: Olympia. WA. Posts: 8,648	Instead of looking to add a second pump I would look into why a pump that's rated at 1720 gph at 0 head is only getting 400 gph on your 90. According to the manufactures specs the 400 gph figure would be at almost 11.5 feet of head pressure. __________________ 240 gallon soft coral tank 50 gallon lps tank