Are sumps noisy?

no.

there are modifications you need to do to make them silent, but there pretty straightforward.

after getting the standpipe silenced, the biggest noise maker will be the return pump.
 
Do not wrap your pump in styrofoam if it is one of the large pumps like the little giant pumps they will overheat. Not only that it could get hot enough to melt or ignite the styrofoam. You will likely end up with a low level hum. You will get used to the noise. It will be background noise to you in no time and you will find yourself missing it when you sleep elsewhere.
 
or you could get a GRI or blueline pump... which you wouldnt be able to hear even with your head in the stand.

:D

i could give you standpipe directions, and pump recommendations once you figure out how much you want to spend, and how your going to setup the water flow to the sump, either a drilled tank or an overflow box.

If you still havent purchased the tank, do yourself a favor and buy a "reef ready" tank. It will come with an overflow and 1 or 2 holes drilled in the bottom. Will make the tank setup far easier and save you some time and hassle.
 
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