[untamed]

Originally Posted by GreenSpottedPuffer

Ok that all makes sense but what about getting the refugium herbie and main drain herbie working together? It seems like it would be hard to work on fine tuning both at the same time, especially if you are starting with both wide open. I guess Im just a bit nervous. If it were just the overflow using a herbie, I would feel fine but the refugium one worries me.

While the two Herbies will inter-relate, it's no big deal. They will inter-relate because they can influence the water level in the sump. If the sump level stays constant, they will be very stable. Trust me, it isn't difficult to adjust multiple Herbies to achieve a steady state.

Remember, you should be able to flood anything, provided your emergency overflows are in place. If the Herbie valves get really mis-adjusted, then the water just flows down the emergency pipes and makes a lot of noise. You adjust them, and wait for the system to achieve a new steady state.

Here's some fun...I won't even attempt to explain this in detail...but I can manipulate the salinity of my system by adjusting the Herbie valve that runs between my small sump and the main sump. Hint: evap water is monitored by a float valve in the main sump. If you can get your head around that one, then you have achieve Herbie mastery!