I would say reseal it. I got a 29 off of freecycle and while it did hold water, it was obvious that it was resealed rather haphazardly. Its a couple hours of labor (give or take) but well worth it. Here are the two things you should think about
1. As silicon ages it becomes brittle. Brittle silicon = eventually leaky tank.
2. Other animals may have inhabited the tank at some point. While this may seem harmless, the constant battle with ammonia from hampsters, etc. will cause you to have to break it back down and reseal it anyway.
I am off the opinion "better safe than sorry." Good luck with your tank! It really isn't that bad to reseal, just take your time and scrape all the old silicon off and make sure the glass is CLEAN before applying the new silicon. I would also add a word of advice. The silicon starts to setup rather quickly once out of the tube. So i would start at the bottom of the tank, and get it as perfect as you see fit (I used painters tape to make sure all my seems were even). Then go to the sides after you are done with the bottom.
If it is anything like the tank I just redid, its got that old school limnated plastic wood crap (Gross). What I did was to spraypaint the rims, back, and bottom of the tank (it was a little beat up as it was sitting in this guys garage for 12 years). Tank almost looks brand new and it all only took me a couple days to accomplish. I used flat black on the rims first, so that the glossy black would stick well (using this method you could paint the rims anything you want including silver, gold, red, blue, etc.).
Good luck on your tank!
SubluxT7:headbang2: