Durso to herbie conversion issue

fermentedhiker · Oct 21, 2018

So I picked up a used 125 gallon RR. Too good of a deal to pass up. It came with the standard dual corner overflows with 1" drains and 3/4" returns.

I plumbed it like a herbie with the left drain being valved to a full siphon and the right drain being the open channel/trickle drain. Got it all leak free and working.

Trouble is the overflow can't handle the output of the dual return pumps. To be clear the drain can handle it, just not the overflow itself. This pushes up the level in the open channel drain to the point that it's more than a trickle. Not a ton of flow but enough to be noisier than I like. Mostly a waterfall sound as opposed to flushing.

Trying to decide on the best fix. I suppose I could put a durso style gurgle buster on the open channel so it isn't as noticeable. Alternatively I could throttle the return pumps back to match what can get through the overflow slots. The best solution(also the most work) might be to get a dremel and make the slots in the overflow bigger to allow more water to flow through.

What have others done to deal with this issue?

Hitman · Oct 21, 2018

I like your idea of using the dremel tool to open the overflow slots. I have no experience with your set up put that’s logically seems like it should work.

fermentedhiker · Oct 21, 2018

Hitman said:
I like your idea of using the dremel tool to open the overflow slots. I have no experience with your set up put that’s logically seems like it should work.

Yeah my only concern is trying to do a neat job of routing them out. Hard to do a whole bunch of vertical lines that are side by side and not notice the screw ups

lmm1967 · Oct 21, 2018

only way to reliably do what you are trying too do is to run a full siphon and trickle in each corner and run your returns up and over the tank.

You won't be able to keep your current setup balanced over the long run and you run the risk of creating a super low (or no) flow zone in the bottom half of the right side.

I'm currently running 2 120 gallon tanks this way and they are dead silent and stay balanced without issue.

Hitman · Oct 21, 2018

May be practice on a cheap piece of acrylic from the hardware store. I know for a fact I don’t have a steady hand to make perfect lines lol

ca1ore · Oct 21, 2018

Not sure I entirely follow. Are you saying that one corner overflow has the siphon and the other corner the open channel? If so, it won't work that way. Both the siphon and open channel have to be in a shared water volume. You will need to do as suggested earlier - dual herbies. This is, in part, why the dual corner overflows stink.

Flippers4pups · Oct 21, 2018

@fermentedhiker,can you post a picture of the inside of your overflows?

fermentedhiker · Oct 21, 2018

ca1ore said:
Not sure I entirely follow. Are you saying that one corner overflow has the siphon and the other corner the open channel? If so, it won't work that way. Both the siphon and open channel have to be in a shared water volume. You will need to do as suggested earlier - dual herbies. This is, in part, why the dual corner overflows stink.

Actually they will. Since the DT has the same level the overflows maintain the same level(or would if the overflow grate wasn't so restrictive). Balancing the flow is no harder than if they were in the same one(again if I didn't have a bottleneck at the grate). The earlier mention of stagnant water in the overflow with only the trickle is a valid concern though. Balancing dual full siphon pipes seems like it could be a little tricky, but if people do it, it must be possible.

Flippers4pups · Oct 21, 2018

fermentedhiker said:
Actually they will. Since the DT has the same level the overflows maintain the same level(or would if the overflow grate wasn't so restrictive). Balancing the flow is no harder than if they were in the same one(again if I didn't have a bottleneck at the grate). The earlier mention of stagnant water in the overflow with only the trickle is a valid concern though. Balancing dual full siphon pipes seems like it could be a little tricky, but if people do it, it must be possible.

Think of each independently. If one will full syphon, the other should as well. The trick with Herbie's is to not have any horizontal drain runs, elbows or as straight as possible to the sump. Gates valves should be as close to the sump as possible.

Pntbll687 · Oct 21, 2018

You can cut away the teeth on the overflow to get more water through.

I would start by cutting every other tooth out, this way you still have something to stop fish from going through.

cromag27 · Oct 21, 2018

missing some key info here. what size are your pumps?

Flippers4pups · Oct 21, 2018

You should not have to cut the weir. If the return pump is of correct size and provides enough flow to the DT, it should provide plenty of flow through the weir to the Herbie.

Can you please provide a picture of the way it's plumbed?

fermentedhiker · Oct 21, 2018

Flippers4pups said:
You should not have to cut the weir. If the return pump is of correct size and provides enough flow to the DT, it should provide plenty of flow through the weir to the Herbie.

Can you please provide a picture of the way it's plumbed?

The weir works fine with the pumps using the stock dual durso. I was trying to do a single Herbie with the left side being the siphon and the right side being the trickle drain. Which forces the full siphon side overflow to take 99% of the flow from the return pumps. Which the drain can handle but not the weir.

fermentedhiker · Oct 21, 2018

cromag27 said:
missing some key info here. what size are your pumps?

Pumps are two rio 2500. They aren't the problem. My modification is what is at issue.

cromag27 · Oct 21, 2018

fermentedhiker said:
Pumps are two rio 2500. They aren't the problem. My modification is what is at issue.

two 782gph pumps, minus head loss and that's a ton of flow for a 125g. make all the drain holes bigger or dial back the pumps.

fermentedhiker · Oct 21, 2018

cromag27 said:
two 782gph pumps, minus head loss and that's a ton of flow for a 125g. make all the drain holes bigger or dial back the pumps.

Yeah throttling is an option. They are the pumps that came with the tank(I pretty much bought his whole setup equipment wise except for the sump and lights). Not what I would've picked but it'll do for now.

I may go with dual herbie's as some have suggested just to make sure one overflow doesn't get stagnant. Of course that means returns over the back

But that could mean sea swirls

but then there's this thing called a budget

cromag27 · Oct 21, 2018

easiest/cheapest route would be to put a gate valve inline with one of the pumps. dial it back just see if that works.

fermentedhiker · Oct 21, 2018

cromag27 said:
easiest/cheapest route would be to put a gate valve inline with one of the pumps. dial it back just see if that works.

It does. shutting off one pump makes everything quiet. Both pumps have output valves built in, so there is that. Just want to do it right the first time so I don't end up with an issue I have to fix after it has livestock in it.

cromag27 · Oct 21, 2018

fermentedhiker said:
It does. shutting off one pump makes everything quiet. Both pumps have output valves built in, so there is that. Just want to do it right the first time so I don't end up with an issue I have to fix after it has livestock in it.

i would use one pump and a splitter to both returns. even with head loss you should have plenty of flow.

lmm1967 · Oct 21, 2018

They are independent and won’t balance properly. As soon as one has an issue ( snail on the drain) you are going to have a flood. The open channel needs to handle the full flow. You are telling us that it can’t even handle half the flow. What do you think is going to happen if one side has s problem?