An internal drain (drilled) will always be better IMHO than an external version and while there is no such thing as a silent sump system the improvements from the days of the original Durso set up have been considerable. Check out Herbie and Bean Animal.
A good place to find out more about sumps is on a reef tank website. They are quite common with marine aquariums but seem to be feared or mistrusted in the freshwater side of the hobby. If you get a drilled tank just set up the water levels properly and you'll have no trouble. The old days of flooded aquariums or sumps is no more if you do your homework.
In short, have no more water available in your sump to be pumped to your display tank than the display tank can hold between the level of the display tank drain(s) and the rim should the drain(s) plug - AND - have enough capacity in your sump to hold as much water as will be drained off your display tank into the sump should your return pump suffer a mechanical failure or power outage.
Have a read here ...
https://gmacreef.com/
Regards,
Stu
A good place to find out more about sumps is on a reef tank website. They are quite common with marine aquariums but seem to be feared or mistrusted in the freshwater side of the hobby. If you get a drilled tank just set up the water levels properly and you'll have no trouble. The old days of flooded aquariums or sumps is no more if you do your homework.
In short, have no more water available in your sump to be pumped to your display tank than the display tank can hold between the level of the display tank drain(s) and the rim should the drain(s) plug - AND - have enough capacity in your sump to hold as much water as will be drained off your display tank into the sump should your return pump suffer a mechanical failure or power outage.
Have a read here ...
https://gmacreef.com/
Regards,
Stu
