I recently picked up a used 300 gallon that previous owner was using with hang over back overflows and I wanted to upgrade to internal overflow style. After reading here and doing few searches on internet im not coming up with to many choices to choose from that I feel will be sufficient for such a large tank. Another option would be to install 2 over flows but not sure this would be best leaving me with 6 drain holes to run to sump complicating things. I have thought about the 36inch modular marine or installing 2 of the 24inch Fiji cube. I’m thinking using one of these 2 models because of the removable internal Side for the obvious easy access due to tank being acrylic top is not open and without removable inside part it would be impossible to clean inside or remove anything from inside it if need be. Here is pic of tank so you can see how I would not even be able to get a hand in a stationary inside mounted weir. Wondering if anyone has any pros and cons with either of these products besides fact of needing large sump to accommodate leak down past bulkheads in an event of power loss. Or does anyone have any other suggestions to use instead or any comments to add. Thanks for everyone’s help