Geckos are pets in Bud's Pets and are recurring antagonists in the show.
There was once a football game with Freshwater High against the geckos. However, the fishes had to go to the gecko tank, which is BURNING hot. The geckos were at first winning the game, due to all the fishes dehydrating cause of no water. The Geckcoach tells Coach Salmons that if he forfeits the game, they will give him water. But then, Milo, as waterboy, comes and sprays the Geckcoach with water. The Geckos lost the game, thanks to Milo and the football team. The Geckos were furious when they lost, and wanted revenge when the Geckcoach told the fishes they were going to build a time machine and make them sorry ("Underwater Boy").
The geckos again competed against Freshwater High at the school basketball team. The geckcoach ordered the team to show no mercy to the Freshwater Fish Hooks. At first, the geckos seemed to be winning, but then the Freshwater mascot appeared. The mascot helped Freshwater beat the geckos on the first game. The geckos, furious, wanted to get rid of the mascot so they could win the final game. However, nobody knows who's inside the mascot. Later, the geckos found out that Milo and Oscar are the mascot. The Geckcoach captured managed to capture Oscar, and put him in the gecko tank until the basketball game is over. Milo went to the gecko tank to save Oscar. He put on a fake tail to fool the gecko teacher. Milo then approached the Hall Monitor. Milo pushed the gecko teacher into the Hall Monitor, saying that she is "skipping class", which caused the Hall Monitor to attack the teacher. After Milo rescued Oscar from the gecko tank, they went back to the basketball game, and thanks to them, the Freshwater beat the geckos again. The geckos were angry that they again lost a game between Freshwater, and before they left, the Geckcoach told them that they will be back next year ("Mascotastrophe").
When the gang went trick-or-treating outside the tanks, they went to the gecko tank, saying "Trick-or-treat" to the Geckcoach. The Geckcoach gave them deoterant for their "horrible fish smell" ("Halloween Haul").
- The geckos were mentioned when the hamsters considered using them instead of fish after Bea pretended to be sick ("Hooray for Hamsterwood").
- A running gag with the geckos is how they lick their eyes. This is because in real life, geckos lick their eyes to keep them clean because they do not have eyelids.
- The Geckcoach's last name is Geckowski.
- Some of the geckos have first names, Tamara, Glen and Marian.