How do I prepare my new tank for an octopus?

[GaiusNero]

Hello fellow ceph enthusiasts. I've kept various freshwater and a few saltwater aquariums over my teens and early 20s. I've recently graduated college, and now have a desire to keep a pet octopus. In terms of my tank, I've come into possession of a 75 gallon Marineland aquarium and stand, which was previously used for a freshwater community tank. From what I can tell, this is the setup I have.
So what can I do to get ready to make this saltwater and also octopus proof? I figured I'd need an entirely new stand for a sump. If possible, I'd like to avoid drilling it, but I will if there's no other way. What should I clean it with? I know about general stuff about cycling it, and letting it mature.

 

[tonmo]

Hi @GaiusNero -- hopefully you'll get some fresh perspective from those with experience within the community, but in the meantime, here are some key starter threads to check out if you haven't already:

START HERE: Tank Talk Forum key threads

Below is a compilation of the some of the stronger threads in this forum, covering core topics. This list will be periodically updated, as will the threads/posts themselves, as new information warrants. https://www.tonmo.com/threads/red-lights.12833/...

tonmo.com