Where's Mr. Sticky?" Abby asked.
"On the side," Mum said. She was busy concentrating on the water. "Don't worry I was careful."
Abby looked on all sides of the tank. There was no sign of the water snail.
"He's probably in the gravel then," her mum said. "Come on let's get this finished. I've got work to do." She plopped the fish back in the clean water where they swam round and round, looking puzzled.