Welcome!

Welcome to PetForums, the UK's most popular and friendly pet owners community. Please 'Sign Up' if you'd like to take part and contribute to our forum.

Sign Up

Green water

Discussion in 'Coldwater Aquarium Advice' started by LB123, Dec 29, 2018.


  1. LB123

    LB123 PetForums Newbie

    Joined:
    Dec 29, 2018
    Messages:
    2
    Likes Received:
    0
    Hi, a few months ago a upgraded to a larger tank, I only have one fish in it, tank is 80l, with one goldfish that is about 6 years old, about 7in, for some reason the water has started going bright green within a week of water change, I upgraded the filter too ( fluval u2), I have added water conditioner and algexit but has not helped, what's going wrong ???
     
  2. kittih

    kittih PetForums VIP

    Joined:
    Jan 19, 2014
    Messages:
    5,084
    Likes Received:
    7,268
    Hi and welcome. When you upgraded the filter did you ensure all media from the old filter was transferred over to preserve all the bacteria ? The tank is extremely small for a standard goldfish. Generally speaking standard goldfish do best in ponds. Gold fish a gig messy fish and produce lots of waste. This waste and the ammonia from it gets broken down by ammonia consuming bacteria in the filter into nitrite and then nitrite eating bacteria convert it to nitrate. The first two are very toxic and the latter is only toxic at high levels. Ammonia, nitrite and nitrate all can be food sources for plant life. In the absence of any or sufficient plants (or bacteria in the case of ammonia and nitrite) to use up this food resource algae which are naturally present in the water in tiny numbers feed on these nutrients and grow in large numbers.

    Given you have such a large waste producing fish in such a small water volume and that you recently changed your filter and have likely upset the bacteria somewhat an algae bloom isn't surprising.

    What are your water test results for ammonia nitrite and nitrate, whats your lighting regime and what is your water change regime?
     
  3. LB123

    LB123 PetForums Newbie

    Joined:
    Dec 29, 2018
    Messages:
    2
    Likes Received:
    0
    Hi, thanks for posting, I usually do partial water changes weekly, and the lighting is off overnight and generally only on afternoon/evenings,I don't have a water test kit but am going to buy one today.
     
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice