Stubborn Blue Green Algae With Weird Water Perimeters

  1. BettaOtto

    BettaOtto Valued Member Member

    So I have BGA in my 5.5G pea puffer tank. I tried black-out, vacuuming, 25-50% water changes every other day. It always comes right back in a day or two. It's been going like this for a couple of months. I don't know if it's introduced by feeding the live black worms (their cup is by the window and the water is greenish), or having potho plants in my HOB filter? The tanks been going since Oct 2016, had two pea puffers polluting the tank to the brownest I have seen, but one died because it kept getting outcompeted, picked at and got no food from the other puffer. I tested the water every week. 0 Ammonia, 0 nitrite and 0 nitrate. And I know the nitrate solution works because it consistently show that my 10G tank has a 5-20ppm (I can't tell what shade of orange it matches, so I assume 20). Any thoughts? Pics below.

    From today:
    Last time:
    7ed753c98569186199bfe8ad9a17a89a.jpg b7832de33e31a8aa0578eb722da73efe.jpg

    Here's the nitrate for the big tank:
  2. KinsKicks

    KinsKicks Fishlore VIP Member


    Have you tried adding an airstone while doing the blackout. They tend to spawn in tanks where there is low O2 and no circulation.

    And how long have you done the blackouts?
  3. Piaelliott

    Piaelliott Well Known Member Member

    Yes, low circulation and low nitrate contribute to the problem. Since you don't have nitrates that could be the reason.
    BBA and BGA - Causes & Treatments - The Planted Tank Forum