Is this normal ?

[Urban Rogue]

On giving him his daily bath we noticed today he had either urinated or poo'd in the bath we left him for 5 mins then once finished we thought it a good idea to change his water so to keep him clean and we noticed this in the image below (wasnt like this before his bath)

Anyhow without being too much of a newbie we think we know what it is but would like to just check thats this is normal

Thanks
Lee