Hydrozons or Hydrozoons: How To spell?
The word Hydrozons is misspelled against Hydrozoons, which is plural of "Hydrozoon"
Hydrozoons has double "oo" is mispronounced as "o"Remember double 'OO' in between the strings hydroz & ns which should not be misspelled with single 'O'
Wrong Spelling:  hydroz-o-ns  Correct Spelling:  hydroz-oo-ns 
Find more incorrect spellings of Hydrozoons to spell right way.