Cycled tank with 0s 20 Gallon Tank

  1. DRock914

    DRock914 Valued Member Member

    My 20 gallon tank is cycled but is reading ammonia 0, nitrite 0, and nitrate 0. If you have live plants in the tank can that cause your nitrates to read 0? 2 weeks ago my nitrates read 5. I was going to do a WC tomorrow but should I hold off since there is nothing to change?
  2. Shawnie

    Shawnie Fishlore Legend Member

    not always with plants, and having a 0 nitrate reading, does it mean you are cycled....but, it could be!!

    what method have you been cycling with and how long have you been at it?
  3. ynaggo

    ynaggo Valued Member Member

    How long has it been since you induced the cycle?

  4. OP

    DRock914 Valued Member Member

    My tank finished cycling about a month ago and I just got the 0 reading today. I cycled with 6 gold barbs.
  5. pepetj

    pepetj Well Known Member Member

    Higrophila difformis (Wisteria) is known to take up nitrates from the water column (as well as other important -for fish also- trace elements). That could explain your reading of zero in nitrates.

    If you've been feeding your fish regularly once your tank cycled, I see no need to worry as long as you keep obtaining readings of zero in ammonia and nitrites.

    I had sustained readings of zero nitrates in my 145gal Tiger Oscar tank when I kept Hygrophila difformis (a lot of them), water lettuce, and water hyacinths. They needed too much light and me to replenish trace elements. I had no problem with that, but when my female Oscar died unexpectedly and the new lady Oscar arrived (she is not plant friendly at all) I had to accept her decisions on aquascaping (it's her tank anyways).

    Santo Domingo
  6. OP

    DRock914 Valued Member Member

    Thanks Pepetj, that makes a lot of sense because my wisteria plants has been growing abnormally fast. I have been feeding them every day.
  7. f

    flyin-lowe Well Known Member Member

    How long did it take the tank to cycle? You said it finished a month ago but I didn't see when it started. I tried to cycle a tank with some plants and 6 black skirt tetras. After almost seven weeks I was still in the beginning stages with ammonia about .25 (sometimes zero) and the nitrite and nitrate never did register (always zero). The bio load of the 6 tetras was low enough that I finally ended up using TSS to move it along. A couple times I got down to zero ammonia and thought maybe it was cycled but then the ammonia would creep back up to about .25 and stay there. Depending on when you added the fish is it possible that it has not cycled yet? Anyone know what the bio load of 6 gold barbs would be, and would it be enough to raise ammonia levels high enough to feed the good bacteria? A fish in cycle would be one of the slower ways to cycle the tank as it is not possible to let the ammonia get really high without harming or killing the fish.
  8. OP

    DRock914 Valued Member Member

    I started with 6 gold barbs and a cory. The cory died a week later and I added a loach and then a Gibbiceps. So the tank cycled with more then the barbs just not in the first 2 weeks, sorry for leaving that part out. My ammonia went up to 8 then down to 0. Next my nitrites went up to 1 then down to zero and my nitrates went up to 10 then down to 5. There is no doubt my tank was cycled. It took about 7 weeks to cycle and the plants were added within the first 2-3 weeks. The tank was set up on 9/25 I think and cycled the week ending 11/14. Surprisingly I lost my cory before the ammonia went up and did not lose one fish while the ammonia was at 8. I lost 5 of the 6 barbs when I put them in my dads community tank so go figure.