Disney's 75G Tank Journal

[Madreefer]

I'd be adding that live rock as soon as you can to start it cycling so you can start adding all the cool stuff. You can also shorten your pcv pipe by an inch or so which will make it so your pump is not touching the bottom or side of your sump. That will stop the humming or rattling sound. Just make sure that the pcv is anchored or supported somehow so the weight of your pump is not putting any stress on your plumbing. But putting rubber on the bottom of your pump is just going to dampen the sound and really should'nt hurt your water parameters. Anything food safe will be good.