Would the 6000 be enough or go with the 12000
I'm running the 6000 on a 150 gallon tank. I'd definitely suggest a bigger pump for a 300 gallon.
Would the 6000 be enough or go with the 12000
I prefer to run internal overflow and drill. I'd be afraid of using the hang on in the event of a power outage. I would need recommendations forban internal boxYes a 50 gallon will be fine for a sump as long as you build it properly for an outage situation.
I use an eshopps overflow box and really like it.
Now just a question why would you not drill the tank rather then use an overflow box
To figure out how much you need to a count for in a power outage situation is 300 ÷ hight of your tank.
so I'm guessing You have to account for about 15 gallons





Have you thought about double 40 breeder sumps and connect them with 2 inch bulkheads. Or you could drill both sumps and use an external dc pump like a deepwater pump