Paint inside tank?

Hi,

Sort of an unusual problem.

I am setting up a bare bottom tank and after painting the outside of the bottom black I see that there is something like a white label which is not inside the tank or on the outside but in between the frame and the glass - so I cannot get to it.
It is unsightly so I would like to cover it up. Would obviously have to be done on the inside of the tank which will be in contact with the water.

What would the best solution be? Black tape will likely come off in time. Maybe silicone some black plastic over it? The easiest would be if I could paint it out with the same spray paint I used on the outside of the bottom. Would this cause any problems so long as I let it cure a few days?

Thanks