Plants I now have with my American Bullfrog Tadpole

[froggyman]

Hello again,

Today I noticed a spot on a leaf from one of my plants with Casper got kinda worried that maybe it dying and I know some plants excrete toxins when the are dying here is a picture in the light where it isn't as noticeable

and here is it in lower light (without the tank light on)

please let me know what you think, thanks