Green water algae and weird test results

[Goldfish345]

Hello everyone, my 55 gallon tank has really bad green water algae to the point where I can’t see my fish ( 3” Oscar and 4” pleco). I installed a UV sterilizer about 24 hours ago so hopefully that starts to help. I did some testing with my api kit and it said 0 nitrite, 0 nitrate and 0.25 ammonia. Why is that? I even made sure my tank was fully cycled before adding fish. Could the algae be absorbing my nitrates, thus the low result? Any help is appreciated!

 

[Caliban07]

The tanks isn’t fully cycled and the ammonia and light is probably causing green water algae.

 

[Goldfish345]

What do you recommend? Should I dose prime or just wait it out? Should I add a sponge from cycled tank or will that make it worse? Thanks!!

 

[Aiken Drum]

How did you cycle the tank? If you are seeing ammonia you arent cycled although its common for 0 ammonia to look like 0.25ppm. Test some bottled water which will be 0 ammonia and compare with the test of your tank water.

Double check the nitrate test. Assuming you are using API liquid test, got to really shake the heck out of bottle #2. Like bang it on the countertop.

Rinsing a sponge from an established tank into the water will help cycle your tank if it isnt already cycled.

Green water is usually the result of too much light. How long are your aquarium lights on for? Does the tank get a lot of daylight on it throughout the day?

Future plans for upgrading the tank? An oscar will quickly outgrow a 55 gallon, and the pleco could too depending on what type it is. Do you know what type of pleco you have?

 

[Goldfish345]

Thank you both for your responses! I will do what you recommended and do the ammonia test on some bottled water later. As soon as I saw green water was an issue I set the lights to be 6:30am-8:30am and 3:15pm-10:15pm rather then on all day. I actually do not have any plans for upgrading the tank. I went to petsmart to get my Oscar (I know what you are going to say but trust me they are much better then my lfs) and then got this pleco to help with some algae. I was skeptical at first that a pleco and Oscar would fit but the person showed me pic of like 2 oscars and a pleco in his 40 breeder. Also the nitrate test does work because I get a reading of 15-20 on my other tanks.