Plumbing drains - dual Herbie?

[Sethjamto]

I just finished plumbing everything on my 300g tonight except the drains. I'm at a standstill on how I should do them. It has dual corner overflows and each overflow is drilled for a 1" and a 1.5" bulkhead.

I'd like to run a Herbie in each. Should I do each drain line with it's own gate valve, or should I tie both siphons together and share a gate valve? Also, should I use the 1" or 1.5" for the siphon?

The return pump is a Reeflo Dart with 6ft of head pressure, so that should put me around 2400gph. I'm also going to be stealing a little of that to feed my skimmer off the manifold (MRC MR-4 dual beckett skimmer), so I'm guessing closer to 1800-2000gph will be going to the returns...maybe less.

[bellis31]

I would gate valve each full siphon drain and so you can tune them both without any trouble.

[Sethjamto]

Have you done it this way? Just curious. I'm trying to simplify the process and am hoping I can control both overflows equally by tying them together with one gate valve.

I'm thinking two valve is the best way, but was hoping people can chime in with experience doing it both ways with pros/cons.

Thanks!

[trilinearmipmap]

I have used two valves on mine for years and it works fine.

[Sethjamto]

Which line should be the siphon and which should be the emergency?

[Sethjamto]

Okay....here's my quick thought of the morning while I was in the garage looking at the tank drinking my first cup of coffee.

Each overflow has a 1" and 1.5" hole. If I run both 1" lines as the main siphon lines and just one of the 1.5" lines as the emergency and cap off the second 1.5" line, will that work? Reason for capping the second 1.5 line and not using it as an emergency also is simply for minimizing the plumbing under the tank. My assumptions on this are that the odds of BOTH 1" siphons becoming clogged are slim to none. If one ever clogs, the other will handle it along with the 1.5 emergency. At this time I would clean out ALL the lines, not just the clogged one.

Thoughts?

[Scffvariable]

I ran both my full siphons to one gate valve. After doing a bunch of research and reading, two valves can be hard to adjust in different overflows and most said to do one.

Personally I would still use the other 1.5" as well just in case.

[Portsie]

I read the entire Herbie thread recently and most people there had issues when using the 2 gate valves. T'ing them together seemed to make dialling it in way easier.

If it was me I would use the 1" drains as the siphon, and both 1 1/2 as emergencies. One more redundancy making a flood that much less likely.

[ca1ore]

I would use the 1" drains as the siphon, and both 1 1/2 as emergencies. One more redundancy making a flood that much less likely.

That is what I would do also.

I have seen dual herbies with dual gate valves as well as where both siphons were tied into a single gate. Both approaches seemed to work fine. I'm a big proponent of using the gravity feeds in place of extra pumps, so I am using dual gates on my 265.