Bean animal overflow for first time...please advise.

[markysgirl]

There was not a temp difference with the giant pump.
I am using an inkbird controller and 2 300 watt Finnex titanium heaters in the sump.

 

[W1ngz]

I think that makes it pretty clear then that the warm sump water isn't getting into the display fast enough to keep it's temperature.

 

[Ferrell]

open up the primary about 1/8 of a turn and wait 5 minutes. Then check it again.
I still think you have too much flow, or there is something else restricting your primary.

I have the same setup (75/30, shadow OF) but using Varios4 at 65% which is somewhere in the ‘hood of 400gph. I vote too much flow too

 

[W1ngz]

So Goldilocks, have you found the flow that's just right?

 

[markysgirl]

I installed the Siccee silent 3.0 yesterday and the flow is much better. The temp seems to be stabilizing but I want to work on the overflow some more. I still can't get a full siphon on the primary without flow down the secondary.
Also, the area of the sump where the return pump lives is really low with the new pump. Any ideas about how to remedy that? I'm afraid to add more water to the system in case of a power outage, I don't want the sump to overflow.
I think I am also going to change the outlets on the returns from the Y dual returns to a single on both sides. And I need to drill holes in the top of the locline connectors so theres a higher siphon break.

 

[W1ngz]

The water level in the return pump section is where it drops due to evaporation. Adding 4-8 cups of water will likely cure that, and changing the water depth above the pump by 2-3 inches can have a surprising effect on the overall flow. The return section is also where you will add any sensor or float valve for an auto topoff for exactly this reason.

-water level in the tank can never drop lower than the overflow weir - unless your return nozzles are pushed too low below the waterline, and then create a back-siphon when the pump stops. Raise them to just below the waterline to stop this.
-water in the preliminary sump chambers cannot drop due to the baffles

If you're concerned about power outages, pull the plug on the return and skimmer. That will show you your highest sump water level in case of a power outage. You're safe to fill the sump to an inch or two below the rim if you need to when all the water movement has stopped, though that would probably be overkill.

Fine tuning takes time and patience. Make tiny adjustments to the gate valve (1/8 turn and smaller), and wait at least 15 minutes to see the result in the water height in the overflow box. If you want the water height a tiny bit higher, close the gate valve just the smallest fraction of a turn and come back in 15 minutes. A little lower, then open it just a tiny bit.
If you need to, you can push the primary fittings a bit lower in the water, or trim 1/4" off the pipe. You should end with just a tiny, silent trickle down the secondary.

 

[W1ngz]

I've been editing/adding to that post for the last 5 minutes... so it might be worth re-reading it.

 

[cedwards04]

Perhaps your primary drain in the overflow is too tall, lowering it may help achieve full siphon without going down the secondary.

The above post is good info. The only thing I will add is that 1/8th of a turn for adjustments is only going to get you in the ball park. Once you are close, extremely slight turns will fine tune it in. Like 1/100th of a turn. The slightest adjustment on that gate valve will have large effects on the small volume of water inside that overflow box.

 

[zalick]

If you see your sump return section get "lower" while adjusting, or vice versa, that water is now in the tank/overflow. It's all a delicate balance.

As @cedwards04 it's a very fine adjustment.

For example, I made a tweek In my plumbing last night and I had to readjust my beananimal. I made my last 1/1000th of a turn before bed and it took 12hrs to fully settle in.

Here's a visual:
I want to reduce my secondary by a single drop of water so I open my primary gate valve by 1/1000th of a turn. That single drop is shifting from the secondary to the primary. The water level in the overflow box is going to slowly lower, 1 drop at a time, until it reaches equalibrium. Takes a lot of time!

It's a tedious process and learning curve but once you get it set right, it's truly set it and forget it! And dead silent.