They are a little over 1" , but wanted to think they were smaller just in case. Don't freak out when I say this, because this tank is basically a little quarantine tank until I get my 180 up. Its a 40 breeder (( korailia 2's if it matter )) I have a TINY blue hippo tang , and a coral beauty. ((BLUE HIPPO IS TINY AND WILL BE OUT IN ABOUT A MONTH)). Then I have a maxima clam, cleaner shrimp and RBTA.