Molly "surfing"

  1. NickW Initiate Member


    I've got 4 mollies in my tank and he's riding current of the filter. He's sitting in the middle of the tank, swimming against the current and basically just staying still.... he's there about 90% of the time!

    The other 3 are fine, swimming about everywhere. Why is he deciding to stay in this position? Is this normal behaviour?
  2. oldsalt777 Well Known Member Member

    Hello Nic...

    Like all species of livebearing fish, it's an active swimmer. Many tank keepers keep these fish in small tanks, and they'll adapt. But, get them in a larger tank with a lot of room to move and they'll thrive.

    Hopefully, you have your Mollies in at least a 30 gallon.


  3. NickW Initiate Member

    They are not :(

    I took the advice of the shop I bought them from. I told them I have a 10 gallon tank and a fighter fish and they pointed me in the direction of the mollies!
  4. oldsalt777 Well Known Member Member


    Some pet store people are just trying to sell you something. It doesn't have to be something that works. Shame on them for steering you in the wrong direction. But, we live and learn. You have the Mollies, so you must keep their water extremely clean, they aren't hardy fish. If waste material builds up, they'll certainly die. So, get a water testing kit that tests for ammonia, nitrite and nitrate. Learn all you can about these forms of nitrogen. You should be removing and replacing half their tank water every three days and replace it with treated tap water, so there's no time for fish wastes to build to a toxic level. Add some individual stems of a floating plant like Hornwort or Water sprite to help keep the tank water clean between water changes.

    Do your research on these fish and make plans for a larger tank.


  5. NickW Initiate Member

    Thanks old. I'll keep my eye out for another tank.

    The cycle hasn't yet been established. I told this to the guy and he said get 4 mollies. Oh well! I'll be coming here for advice from now on.

    I will get the api master test kit as soon as pay day arrives. And will keep doing water changes every 3 days until the cycle is complete and keep a keen eye on the nitrate levels from thereafter.

    I have some biohome in my filter and have also used bacteria spheres so hopefully it will be up and running in the next few weeks.

    I've made a makeshift gravel syphon with some tubing and a cut in half Fanta bottle. It seems to work well.

    The guy at the shop also told me never to do water changes... ever!