h2o just add water season 4?

There has been alot of rumours that  h2o just add water season 4 is coming out and that Emma is back and it leaves the four mermaids Rikki, Bella , Cleo and Emma. I'm about 70/80 % sure that there's not going to be a next season because, lets be honest Cariba, Phoebe, Claire and Indiana are a bit too old to be acting as teens in a mermaid show. Also there all in the middle of shooting different movies and series.
What do you think? Will there be a season four of h2o just add water or is it just a made up story for fans?
Leave a comment bellow on what you think.