Unusual FBT Colouring (Pictures included)

[Amber Gyore]

While cleaning the enclosure today I noticed Hugo had some odd discoloration on his side. I thought perhaps he had injured himself and it was a bruise of sorts, but I looked closer and it's on both sides of his tummy. Is this normal?

[Pezoneden]

did it just appear or could u might have just not noticed it before? One of my frogs has very vibrant green colors but has odd brown patterns like that in weird places (one of the reasons i bought her.) So i mean i wouldnt worry about it unless ur 100% sure it was not there before. Im no pro though just giving the best advice i can

[IrishRonin]

I wouldn't worrie about it if it's on both sides like you said unless it starts to spread.

[Amber Gyore]

Also, I've noticed my toads haven't gone into their water since I switched their dark gravel with light gravel. Are they doing this because they don't like the fact that they can't camouflage with white pebbles? They seem to be staying in their log, or at the dark shoreline.