Will this cause damage ?

[DKoKoMan]

Ya 50% less water will make a huge difference in weight and consider it a large WC

[Millepora_Maniac]

Hi Man,

I did this myself twice. once on a 180 gallon, and again on a 90 gallon, both times i drained the tank down as far as i could, then just removed it. I installed my new sump, then jacked the sagging cross brace up and slid the old piece back into position, glued it and screwed it on.

Although i did it multiple times, i was paranoid and having heart palpitations each time i did, so i still don't recommend it. Do it if you have no choice is my advice.

Cheers!