Ammonia Reading In Cycled Tank? Why? How Do I Fix?

  1. sross78 Member Member

    I just tested the water in my 30 gallon cycled tank for the 1st time in a few weeks and got an ammonia reading of 0.25. I had a 0 reading for months!! I immediately cleaned the filter, did a 50% water change and vacuumed the substrate really well. I also treated with Prime right after and will continue to do so each day until its gone.

    Water tests as follows:
    Ammonia 0.25
    Nitrite 0
    Nitrate 10-20 ppm (so hard to tell the difference on chart but healthy either way)

    Not sure how this could have occurred other than possibly overstocking the tank. No fish have died or acted stressed out, in fact they have been acting like one big happy family. So my question is, am I overstocked?

    Here is the current stock/size:
    1 swordtail - 4 inches full grown
    1 dwarf rainbow - 2.5 inches full grown
    2 bosemani rainbow - 2.5 inches not full grown yet but will be moving to 55 gallon at 3.5 inches
    4 dwarf red platy - 1 inch full grown
    7 cardinal tetra - 1-1.5 inches each almost all full grown
    2 julii cory catfish - 1 in each max 2 inch

    Based on my calculations that is less than 30" total and with the bosemani being moved in a few months while some of the others grow a little more, i thought i was fine.

    Maybe I just hadn't cleaned the filter and vacuumed the substrate well enough in the past month???
     
  2. goplecos Well Known Member Member

    I would do another water change but the Ammonia is nowhere near toxic so it's not an emergency. The main reason that I am replying is because you have some stocking issues. Rehome the Sword with the rainbows and get him some females. And get the Corys some friends, 3 is the minimum 6+ is better.
     

  3. sross78 Member Member

    I just input the #'s in the aqAdvisor and it says:

    Warning: You should add more aquarium filtration capacity.

    Your aquarium filtration capacity for above selected species is 89%.
    Recommended water change schedule: 30% per week.
    Your aquarium stocking level is 101%.

    Should I just add a 2nd small filter?

    I have tried giving the male swordtail both male and female friends and he chased them relentlessy into submission/hiding so I rehomed them and replaced with plats/tetras. He seems super happy as the king of the tank and has never liked ANY other swordtails lol.
     
  4. JoJe Member Member

    Not the answer you want to hear, but don't panic. A 30% change per week is only a little above the recommended 20%, and 101% stocked is only slightly overstocked as long as the fish aren't staying in there as adults like you said. It does beg the question what is your filter however? It would be near impossible to have too little bio media unintentionally if you bought a filter designed for scale. Note that a single Nitrosomonas is ~4 microns long. A LOT can fit on a little bit of media.
     

  5. Over It Well Known Member Member

    You would ideally have your stocking level at 80-90%. But that's neither here nor there. I would agree with getting a second filter to go along with the first. You pretty much can't have too much filtration. You want to aim for a filter or 2 that is for twice the size of your tank. So if the filter you have now is meant for a 30 gal. get another filter meant for a 30 gal as well. Or you could even go a little larger.
    Lastly additional water changes will help. You might have to continue to do more frequent water changes till your Bio-filter can catch up or you rehome/remove some fish.
     
  6. sross78 Member Member

    I have a Fluval U3 (rated up to 40 gallons but i doubt it can do that much) and I just added a sponge filter as well. Hopefully they can catch up. I have actually been doing 40-50% water changes on the tank every 5-7 days so they are getting plenty of fresh water lol.
     
  7. JoJe Member Member

    Ok. You are right that is probably not enough turn over to be ideal. To be safe, a second filter wouldn't hurt, but some plants are also an option if you don't have them already, as they will help consume nitrogen compounds, and look less ugly than a second filter.
     

  8. sross78 Member Member

    I have thought about plants but my substrate is just fake not real sand, wouldn't they die?
     
  9. goplecos Well Known Member Member

    If your Swordtale is a dominant male you can keep him by himself, I had the same problem with a molly. I would still strongly recommend getting 1-4 more corys. My plants do fine in gravel with some Seachem root tabs, and a little extra API fertilizer.
     
  10. JoJe Member Member

    Just do low light simple plants like Java Fern or Anubias. I have plants in simple gravel in my 4 gallon and they grow fine (Lindernia and Java Fern).
     

  11. sross78 Member Member

    great, thanks for the suggestions. I don't think I can add anymore cory's due to my current stocking though.