Noisy Overflow & Sump Fluctuation Issues

[Arrow1oo]

So I’ve been working on getting my 300 gallon tank up and running (8’ long x 2’ wide x 29” high). The plan is to house SA Cichlids so I knew I needed good filtration.

My tank has an internal overflow in the middle behind a weir and has 4 bottom drilled holes:

2 3/4” returns on the outsides
2 1” drains in the middle

Naturally, I set this up with a herbie and for the most part everything works well.

I have two jebao dcp-6500 pumps and I am using a 75 gallon tank loaded with poret foam as a sump.

While the sump works fine, I’ve been having a hard time consistently tuning it.

I’ve been keeping the pumps at 60% and I tuned my gate valve on my main drain to match that flow rate, but every time I come back the next day the water line behind the weir is either a bit too high or a bit too low and causing some noise.

Additionally, when I go to adjust my gate valve I can hear slight gurgling which tells me something might be off.

I’ve been through this process a few times but no matter what I always end needing to make adjustments which seems wrong.

Through the research I’ve done, the only potential solution I’ve found is threat evaporation in my sump effects my pumps return rate every so slightly. But I’m not sure.

If that is the issue, I can always add and ATO.

Would love some help on this.

 

[M3AN ONE]

Herbies are hard to tune so that they are dead silent. My suggestion would be to run both returns at full tilt and the drain pictured on the left leave it completely opened up since it has the elbow that will be below the water level it will be silent. On right drain slightly open it just enough were you can control the water level of the over flow chamber. Only issue is if a drain is clogged there is nothing you can do. I have 3 drains the last one is a backup thats is above the water level so if one clogs it will kick in. When that one is running it makes a loud sound as the water gets sucked in.