Setting up the outflow Box


Reefing newb
Hi, Being new at this i am asking if you could could answer a question for me? The outflow box on the aquarium has three holes at the bottom. Two holes are 1” and the third hole is 2”. Are the two 1” holes for the return to the sump and the 2” hole for the pump? Also there is a two inch hole just below the top of the outflow box leading into the tank itself . Is this for the pump putting back water into the tank? Any help you could give is greatly appreciated.

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That's perfect for a "bean animal" .... one of the safest ways to drain without destroying your floors.

The 2 inch is your emergency overflow pipe. This stays dry unless there is a legit emergency.

The 1st one inch line is your main drain. Set it up with plenty of vertical drop and use a gate valve to adjust siphon flow.

The 2nd one inch line is your "wet" emergency drain. It will have just the tiniest trickle when operating correctly.

Google began animal
Google herbie drain