Major Issues With 55 Gallon Tank! Help

Discussion in 'Cleaning and Maintenance' started by Karenk2, Apr 22, 2019.

  1. Karenk2New MemberMember

    Hi- I have a 55 gallon Aqueon tank stocked with 6 Rainbow fish, 2 gold weather Loaches, 4 Cory Catfish. This tank has been running for about 3 years and it has now crashed, I believe with old tank syndrome. I do water testing everyday and water changes, around 15% sometimes more. The testing today came up with: PH. 6.0, ammonia. 0.25, nitrite 0.25 ppm, nitrate 40 ppm. These are the usual values I’ve been having for around 2 weeks- not sure what to do!
  2. mattgirlFishlore VIPMember

    I would start with much bigger water changes. How often were you doing 15% water changes? Were you cleaning your substrate?
  3. oldsalt777Well Known MemberMember

    Hello Karen...

    I can tell you 15 percent water changes aren't nearly enough. You still leave most of the pollution in the tank, for the fish to add to before the next change. You've likely got a build up of waste material in the water and nitrogen will drive off oxygen very quickly and make the water conditions unlivable for the fish. Your fish have adapted to the high nitrogen in the water, so a large water change at this point would be fatal to them. If you want to keep the tank running, you need to improve on your tank management. Start by gradually removing and replacing more tank water every week, while slowly reducing the amount you feed the fish. When you change the water, start vacuuming a small area of the bottom material. You need to work up to the point you remove and replace half or more of the water every week. This will eliminate the need for testing and guarantee a steady and healthy water chemistry for the fish.

  4. mattgirlFishlore VIPMember

    @oldsalt777 has given you some very good advice to get this tank back on track.
  5. Karenk2New MemberMember

    Yes, thanks! Do I still do daily water changes?
  6. mattgirlFishlore VIPMember

    What is the PH of your source water? that reading of 6.0 is a big red flag for me. When it gets that low all of your ammonia reverts to ammonium so is not very good food for your bacteria. That could be why you are losing your cycle.

    I would start gradually increasing the amount of water you change out daily. It has taken time for your tank to get to where it is now and your fish have acclimated to it very slowly. You need to change it slowly to allow them to acclimate to the new perimeters.

    I would do 15 today, 20 tomorrow, 25 the next and so on until you get up to 50%. Only then would I be comfortable enough to stop the daily water changes.

    If you've not been doing so you need to slowly start cleaning your substrate. Do just a section of it with each water change.
    Last edited: Apr 22, 2019
  7. oldsalt777Well Known MemberMember


    Daily, small water changes won't have much of an impact on the cleanliness of the tank, because the fish are consistently adding to the pollution One, slightly larger water change performed weekly is the best way to the water conditions. The bottom material is very likely holding a considerable amount of waste material and this contributing to the poor water. Make your weekly water changes gradually larger and use your siphon to clean up the substrate. This slow improvement in the water conditions won't be a shock to your fish and their health will also slowly improve.

  8. SkavatarWell Known MemberMember

    doesn't sound like you're overstocked. so weekly 50-75% water changes should be plenty. and vacuum the substrate.

    small waters changes not only don't remove enough wastes, you're also not replenishing vital minerals and micronutrients.

    what's the GH and KH of your tank? what's the GH and KH of your tap water?