trim

I was cleaning my 55g aquarium and I flipped it over to inspect it further. It seems that some of the bottom trim flexes a little when I try to push against it. Is this structurally concerning? It doesn't seem to leak from what I could tell - it's been holding water for days.

So I'm halfway done with making my foam Rock wall. So far it's turning out great but I'll have to cut it apart to get into the tank. Unless I can get the top trim off of my 150g. Has anyone found tried and true methods for this without ruining anything? I just thought a heat gun and putty knife...

So I have this nice 150 gallon tank but the glass has a big chip in the corner. I was able to get a new piece of glass the exact size and I am planning to switch the panels out (the big side panel). ive never changed aquarium glass before let alone a massive one like this. Is there anything I...