First off WELCOME to our OBSESSION!!!!
What a FIND!!!
AWESOME TANK AND STAND!!!!
I have been dealing with aquariums for 25+ years both as a hobbies and working in a friends Fish Shop, and I learned A LOT form him ( shop owner)!!! SO I would 4 SURE tell you NOT TO MESS WITH THE SEAMS or SILICONE!!!
Once silicone is cured new silicone WILL NOT ADHERE to it!!! So IF you have a leaky seam you will have to reseal the entire tank! Meaning you have to remove ALL the silicone from the tank even what is between the panes of glass, and redo all of the seams at the same time so it will be leak free!!! Also this info comes from the owner of All Glass Aquariums, the main holding strength of the seams is what is between the panes of glass, and the silicone that is pressed into the corner is to reinforce the silicone between the panes! It took me seeing him redo a tank to understand it but it is TRUE!!! That tiny amount in the seam does the majority of the sealing! He said when they first started making tanks they used smaller amounts of silicone so it would "look" better, or so he thought! They got many complaints about the small amount of silicone on their seams and people didn't think they would last, so they did what the consumer wanted and used more silicone!
ON a tank the size of the one you have I wouldn't even attempt to reseal the tank myself, and I have ( for fun) resealed a few small tanks I bought from a LFS because they were leaking. They would replace them rather than take the time to reseal because their time was money! the first few I did was a big learning curve, because you have to get all of the seams done before the silicone sets up! So IF you do have a leak I would check with your LFS to see if they know anyone who reseals tanks!
Secondly, I also learned , the hard way, that the overflow boxes built into the aquarium serves a few purposes. First it removes the upper layer of water where most of the proteins and other waste tends to build up. Second, and this is one some people don't think of, it protects the piping and bulkheads from being hit by rocks, big fish, or whatever, and causing the bottom pane of the aquarium to crack and break!!! One of the LFS will often drill the bottom of a aquarium and just use bulkheads and PVC for the drains and returns with NO "Overflow" installed around the pipes, and I know of a few people who have had rock work knocked over into the pipes, either by fish or when they were stacking the rocks, and the tank bottom broke out of the aquarium!!!
Lastly it does hide the bright white pipes most use for drain and returns! Alot of people have used Krylon Fusion paint to coat pvc, and it does work, but it will usually chip or flake off when cleaning it. At least that is what I have read hear and other forums. I am still going to try it for myself to try to hide my spray bar in the 40B I am working on!
Oceanic tanks are some of the best aquariums out there, at least for lasting what seams to be forever, so I would just try to clean the seams as good as I can without scraping into the silicone! Once the tank fills and Ya get plants and livestock in it the small bit of algae won't be very noticeable anyway!
The "hood" is pretty short for hiding lights and stuff, but that is the way Oceanic built them for some time. I think they are building taller hoods now that flip up from the front so it is easier to feed and work on the tank. Since you are painting the stand I would just build a hood that you like and paint, or finish, it like you did the stand! If it was going to be stained it would be hard to match the base without striping the stand and finishing it and the hood at one time! I bought a 110g X-tall Oceanic tank about 10 years ago and tried to finish the hood like the stand, and I would up striping the stand and hood and refinishing them both to get a good match! It was 48"lx18"wx30"t, and while it was a AWESOME TANK, I couldn't reach the bottom to plant plants without getting most of my upper body wet! And just having my 3rd back surgery, I figured I better sell it before I fell off the tank when trying to plant and having a 4th surgery!!!
I would do a search of the journals for wet/dry filters or sumps to read up on how everyone has used their sumps for planted tanks to keep from off gassing the Co2 out of the water too! There are a few detailed threads here about sumps that will tell you exactly what ya need to know. I too would reinforce the floor if you are on a pier and beam foundation!!! Our house is a pier and beam, and my 55g is pushing its limits, and it is on a outer wall too! If Ya walk close to the tank you can see the surface start waving!!!
So I am going to send my 18yo Son under the house to block it up, so with the 210g I would for sure check on it!
Other than that HAVE FUN WITH IT!!!! Also READ, READ, READ, all you can here, and you should do just fine! And feel free to holler at us if ya got questions, as that is how I learned and started out with the planted tank obsession I have developed!!! So get Your wallet out, and have a blast!!!
Sorry for the long post too!