seals on new used tank

[Elwood]

I just bought a used 90. The previous owner used a standard shop light with a canopy. Resulting in brown algae. To clean this he scraped and scraped. As a result he lifted the edges of the caulking all around the tank. Some I have been able to cut away without getting to close the main body of caulk. However, other areas have algae under the caulk all the way to the thick part of the caulk. If I trim that I will leave a section of caulk that doesn't have the thin side flair of caulk that seals against the glass.

How severe is this?
If I reseal how do I ensure a good seal between new and old sections of caulk?

 

[Stratoquarius]

I actually just resealed a 224 gallon tank this weekend and I can tell you its not fun.
you have to remove all of the visible silicone and residue and scrape into where the glass meets to make a little groove, once you've done this fully you reseal it with new Silicone.
the main problem is that the new silicone won't stick to the old silicone, so you must remove all of it. Out with the old, in with the new.

 

[Elwood]

How do I patch a spot?

 

[Stratoquarius]

If you have one area you want to reseal, you coudl fully remove the silicone from that area and reseal, BUT i'm unsure if that will effect the integrity of the tank. because its supposed to be one full solid seal, to make it waterproof. You would have to find out if anyone else has had success doing this. Good luck anyway!

 

[AQUAMONSTER]

A 90 is a easy reseal job. Just redo the whole tank. Use a plastic spoon to form the seals and tape to make your seal look nice. Very easy job and will make the tank better than before...