Sump/Return Pump Question
 

Over the last... several... months I have been collecting pieces to set up a new aquarium. I have a 50G Tank and a 20G Sump currently and an Eheim 1262. Question is, is that an incredibly high amount of flow, and will the eheim be fine in 8"ish of water?

you dont even need that much but yeah it will be fine. You will need an ATO to keep your water level consistent though. You can put a valve on the pump to turn it down OR tee it off to run some reactors and divert a portion of the flow.

The pump was bought before the tank as I was originally going for a 70g tank. Do you think it would be better to get a smaller pump or throttle it back one way or another?

Just stick a valve after the pump and you can throttle it back and find your sweet spot

you will have some head loss and depending on how you set-up your plumbing further losses from 90's and what not. Just throttle it back or tee it off to recirculate back to the fuge or a reactor. You dont need to downgrade :D

The 1262 is certainly a little louder than their smaller models. It's certainly more than enough flow. I run one on my 110g system.

1262 is probably too big for a 50G. You can throttle it back using a valve but why waste all the power. Buy a proper return pump with about 3x-5x turn over of your display tank counting all the head loses.
FYI I am using a 1262 on a 180G.