Long sponge urchin turning dark purple

[keddre]

when I got my urchin a month or two ago, he was all black with the blue spots, like normal. However, after a few weeks he picked up a purple hue but I wasn't worried as it was likely just him making his poisons, but now he has picked up more and more of this purple to the point where I'm wondering if this is normal. Thanks.

 

[Mr. Bill]

If he's eating, acting normal, and not shedding spines, that's a good indication he's ok. Could it just be coralline? It's not that uncommon.

 

[keddre]

If he's eating, acting normal, and not shedding spines, that's a good indication he's ok. Could it just be coralline? It's not that uncommon.

He is acting normal; however, I'm pretty certain it's not coralline