So earlier tonight I was looking checking out my small 5 gal refugium/ sump under my tank and noticed this bright red smoosh on the glass. Using the light and camera on my phone I was able to get a better view of what it was. It was a small sail with a blood red body and jet black shell. It was in the same location as an emerald crab, that towered over the snail. Any ideas of what it is???? I'm not to worried about it getting into my display and will probably keep it in the sump. Just curious is all.