Thanks for the reply Hari. That seam to the right is the one I'm talking about. It's a bead of #40 that I did. It recently started turning while along the sides.
I see it now, got confused with the reflection, i did my 300g few months ago, i don't see any discoloration yet but as
B
BichirKing
suggested it should be fine. i went crazy with weld-on as i had a gallon kit which was expiring so all my beads were atleast 1 inch.
In regards to the floor, i have similar issue concrete slabs underneath and leaning arond a inch on one end, i didn't like the angled shims so went with 1 inch treated wood running across the depth of the tank and made some thinner ones for the entine width of the tank, got a
7 foot stabila level and got everything figured out, still not happy so got a digital level, now i am 1mm off on one of the side which i don't think its all set now.