>> Temperature check!
>> On it! Eighty-nine cyber degrees.
>> The temperature was 85, and now it's 89. That's four degrees hotter. Note -- At 89 degrees, the other fish are leaving.
>> ♪ The hotter is gets, the more polluted the water, so tell your merson and tell your merdaughter ♪ ♪ If the temperature gets to 100 degrees, we all must move ♪ ♪ We all must leave
>> Leave Mermaidos?
>> But Mermaidos is my home!
>> It looks like that crazy machine is heating up the water!
>> Ninety-seven degrees!
>> Three more degrees and it'll reach 100.
>> Then everyone will be forced to move away!
>> That's not going to happen, Eugene. We'll stop them.
>> Looks like the water goes up the hill in buckets, then down through a hole in the tank where it gets heated and back down this hose.
>> And into our water! If we can just clog up that hole...
>> Didge, do you have something round?
>> Maybe a ball?
>> We need a bigger one.
>> How about this?
>> [ Gasps ] Slimey's favorite ball!
>> Perfect, let's go! ♪♪
>> Woo-hoo! ♪♪
>> Whoa! Oh, no!
>> Hey! Oh, no! I got it. Nezzy, catch!
>> Here you go, Jax.
>> All right. Woo-hoo!
>> All right! ♪♪
>> Did you ever have the feeling that things were about to go terribly wrong? ♪♪
>> Ah! Ah! Ah-ah!
>> This is not getting any hotter! Why is the water not getting hotter?
>> No need to shout, boss. We're right here.
>> Aah! Ugh. I'm surrounded by incompetents. Ooh!