I would like to re-seal my old 35 gallon flat back hex. Any sugestios would be appreciated.
Thank you.

whoa, a hex is gonna take a little more work than a standard but resealing is easy in most cases.
1) with a safety blade srcape off ALL of the old silicone.(including under the rim which is the cause of most leaks)
2)use a mild/natural solvent such as lemon juice or vinegar to remove any residual residue left
3) rinse and dry extremely well
4) useing an aquarium silicone(make sure the silicone does not have a mold inhibitor such as kitchen/bath silicone as this could kill your fish) simply reseal all the seams where the old silicone was.(you can get a silicone tool to keep it perfectly uniform in the corners)
5) make sure to cure the silicone for a few days before refilling(check silicone curing time on the product being used)
6) refill, cycle and enjoy your beautiful tank and fishes

DION

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also check all the seams to make sure there is no water creep in them salt or fresh if you see a seam that is irregular you may have to pull that entire pain of glass and reglue the whole thing i have seen people that think they needed a reseal bit turned out that they needed to reseal the entire pane of glass just my 2 pennies

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