Think of the personality of your fish. for example:
If it is fast call it speedy, zoom, lightening
if its slow and fat call it chubby, bubbles
if its friendly give it a name of one of your friends. Like Molly or Ginger
if it is big and colourful give it a grand name like angel or a royal name
You wanted some spongebob names . dont use the exact ones of spongebob. try these:
Crabby (mr crabs)
Spongey (spongebob)
Sandi (sandy spelt diffeently)
Patty (Patrick)
Squidly ( squidward)
Pearl can be kept as pearl.
If you want separate names try Minnie or Bert, Lynny, Gem .
Hope this helps.