Re: My 150 gallon build--In progress..
ya the scs1200 is definitly a stronger bond. Ive always had a hard time locating a local source for it though. I normally use the GE brand silicone that actually says on it "aquarium safe". Dont think the SCS1200 is really needed just to reseal, the beads along all the inside corners are not structural.
IMO its a good practice to reseal any used tank you buy. For instance if a tank is treated with copper, the silicone actually absorbs it, and can leach it back out. not to mention obvious issue of leaking.