90g with 3/4" Herbie return pump

[discoscrew]

Picked up a new seapora 90 gallon reef ready tank. Going to convert the durso type overflow it comes with to a Herbie. Now the main full syphon line will be 3/4". I've read that the max flow will be about 600 ish gph. I've been eyeing a Reef Octopus Varios 4 DC thats rated for 1050 gph. Would that pump be a good match? Head will be 4 feet or so.

 

[Reinboordt]

I’m far from an expert but I’ll let you know what has worked for me.

My tank is about 63g filled (up top) and about 30g in the sump.
When I got the tank it also had a loud gurgling durso overflow. I added an additional return line from the pump with hose and then turned the two pipes that formed the durso into a bean animal type system. One line is an emergency overflow and sets the water level height of the display tank, the other line is always in full syphon. They both go to the same compartment in the sump.
The overflow line does not have a gate valve as it needs to allow the overflow.

The full syphon line is connected to a gate valve and I use a jebao DC pump that I can adjust the output to match whatever the gate valve is at.

Turn off your pump and let the water drain into the sump. Whatever that level is at mark it so you know to always have less than that, this way if you lose power the sump will not overflow as it will only drain until the submerged full syphon line is above the surface.

I believe something similar would work for you. Bean animal + Gate valve and DC pump.

My tank is quiet and efficient now.

 

[UncommonSense]

. I've been eyeing a Reef Octopus Varios 4 DC thats rated for 1050 gph. Would that pump be a good match? Head will be 4 feet or so.

Yup, that’s right in the sweet spot for 3/4” plumbing at that head height!

(660gph @ 4.8ft head)

 

[discoscrew]

Yup, that’s right in the sweet spot for 3/4” plumbing at that head height!

(660gph @ 4.8ft head)

I'd need to run it at 100% all the time for that though correct? I wonder if I should bump up to the next size up the VarioS 6

 

[UncommonSense]

I'd need to run it at 100% all the time for that though correct? I wonder if I should bump up to the next size up the VarioS 6

100% throttle on the Varios 4 will be 10%-ish more than your 3/4” drain is physically capable of flowing, and is already ~6.5-7x display turnovers per-hour!

A larger pump would never be able to safely run at full throttle, even the Varios 4 will likely only ever need 100% when dirty!

 

[discoscrew]

100% throttle on the Varios 4 will be 10%-ish more than your 3/4” drain is physically capable of flowing, and is already ~6.5-7x display turnovers per-hour!

A larger pump would never be able to safely run at full throttle, even the Varios 4 will likely only ever need 100% when dirty!

A larger pump would definitely need to be turned way back. I guess what I'm wondering is would it be better on the life of the pump to run a larger one at 40% all the time vs running the 4 at 90%. I have no experience with DC pumps at all and thanks for your help here. Been out of this hobby for 20 years.

 

[UncommonSense]

A larger pump would definitely need to be turned way back. I guess what I'm wondering is would it be better on the life of the pump to run a larger one at 40% all the time vs running the 4 at 90%. I have no experience with DC pumps at all and thanks for your help here. Been out of this hobby for 20 years.

I was out for a few years, myself… so I get it!

The general consensus with DC pumps is that they seem to perform best (power efficiency, noise, etc) at roughly 80% power!