I have seen a 75 gallon with a cracked end glass be repaired in this way.
A peice of 1/4 glass was cut to fit inside the tank and with measurements to fit tight. The silicone was then stripped from the inside of the tank. skimmed the broken pane with silicone and stuck the new peice of glass to it. After the silicone had cured, new silicone was applied to the rest of the seams.
Even if ya the repair atempt fails at least you'll grab some experience which, with monster fish keeping, could be valuable down the road.
A peice of 1/4 glass was cut to fit inside the tank and with measurements to fit tight. The silicone was then stripped from the inside of the tank. skimmed the broken pane with silicone and stuck the new peice of glass to it. After the silicone had cured, new silicone was applied to the rest of the seams.
Even if ya the repair atempt fails at least you'll grab some experience which, with monster fish keeping, could be valuable down the road.