Trouble With Cycling My 75 Gallon Tank

Discussion in 'Aquarium Nitrogen Cycle' started by Vindicare, Aug 2, 2017.

  1. VindicareNew MemberMember

    Hi Everyone,

    I am new to the forum. Now I have been a aquarium hobbyist for about 2 years and I have never run into this kind of dilemma before. Hopefully someone here might be able to assist. I apologize for the long post. I want to provide as much information as I can.

    I have run into some problems with my new 75 gallon tank. Here is a bit of background on this tank. I started setting this tank up just over three weeks ago (July 13th) I used 100% RO water, as my house relies on a Sodium based Water softener to treat the town water that is connected to the house. Equilibrium was added to the tank to replenish the stripped nutrients.

    The GH is 10 degrees (after Equilibrium is added) and the KH 5-6 Degrees. My PH has fluctuated a bit over the 3 weeks going from as low as 6.8 to as high as 7.4. The GH and KH have remained constant the entire time since day one.

    I seeded the tank with live plants taken from my already cycled 10 and 30 gallon tanks. I used Eco-Complete for the substrate and I also added Tetra Safe Start Plus to help establish the tanks bacteria colony accompanied by a small school of Tiger Barbs (5 of 10) to help the tank get established.

    Now here is where I am a little concerned. In my past experiences when using Tetra Safe Start Plus with the 10 and 30 Gallon tanks, my tanks would cycle within a week. This 75 Gallon tank seems to be taking forever, furthermore, I have not seen any of the classic Spikes in the Ammonia or Nitrites. The highest spikes I have recorded for these have been 1.5ppm for Ammonia and 2ppm for Nitrite. I have done a few 25% water changes over the course of the 3 weeks when I first see these spikes appear, and I have also been adding doses of Prime to detoxify and bind the Ammonia and Nitrites for 48 hours, to allow the bacteria to do its work. All of my Barbs are active and showing no signs of stress.

    Now yesterday after testing the water I got the following readings:

    PH- 6.8-7.0
    Ammonia- 0
    Nitrites- 0
    Nitrates- 20-30ppm (can't be to sure where it lies exactly)

    Unsure if I did the testing wrong, I tried it again a few hours later and got the same readings. So with that being said I got the impression my tank had finally cycled.

    This morning when I woke up, I did another test just to make sure the tank was truly cycled and before I begin moving fish into this new home.

    My readings from this morning were:

    Ammonia ~0.75-1ppm
    Nitrite- 0 ppm
    Nitrates- 20-30 ppm

    Any ideas as to what might have triggered this sudden ammonia spike? Did my cycle get restarted? None of my fish have died. My only thoughts that could be the culprit is food and fish waste or that the Prime doses are starting to unbind with the ammonia.

    Thank you for your help!

  2. abheeshsValued MemberMember

    From my understanding, Prime should only be used to save the fish from dying. It will bind the Ammonia and the bacteria won't have anything to work on.

    1ppm Ammonia is fine as long as it gets reduced to 0 within a day. Test again after 24 hours and see if this changes. As you said, maybe this is from the Prime binded Ammonia.

    Side note, 6.8-7.0 is a huge range for pH. Maybe you should get a more accurate reading. If it is actually fluctuating this far, you should not add fish or be very careful to test everyday. 0.3 change can cause shock to fish.
  3. OP

    VindicareNew MemberMember

    Thanks for the reply! Okay I will do a test when I get home to see if the ammonia drops back to 0 when i get home. If it doesn't should I do a 50% water change?

    I say 6.8-7.0 because I am partially colour blind and the PH colours on API colour chart are very difficult at times to distinguish between, same can be said for the lower levels of Ammonia and Nitrites. But that said i have seen it fluctuate up to 7.4 which is much worse than 7.0. But I get your point, is there anything I should do to try and get it more stable? I am not sure what to do with it considering my KH and GH in my tank have been constant at 5 and 10 degrees ppm.

    Thanks again!
  4. abheeshsValued MemberMember

    No water change right now, Tetra can survive 1ppm one more day. If it doesn't drop, then you may not have enough bacteria in there. You can try Seachem Stability instead of TSS. And, if it still says high, make sure to do a Prime or water change.

    Maybe you can take your water to a LFS so that they can tell you exact values. Fluctuating pH can be coz of lot of things. Like your substrate stabilizing, driftwood etc. You can up pH using baking soda (temporary) or crushed coral (continous), but I would take couple of water tests over next week at a LFS before doing anything to the pH.
  5. OP

    VindicareNew MemberMember

    So to give an update. When I got home from work and did a water test. I got the following readings.

    pH: 6.8
    Ammonia: 0.25ppm
    Nitrites: 0.10/0.25ppm
    Nitrates: 30ppm

    I went to LFS and told them of the situation. They are wondering if I don't have enough bio media for my bacteria to cling to within my canister filter. I am using a Fluval FX4 and the only Biomedia I added to the filter at the time of start up was the media provided by them. I can't say I have ever been in a situation where I had too little Biomedia in the tank... so I wouldn't know if it could be a trigger for a cycle to stall. Nevertheless i ended up picking up a 1L container of Seachem Matrix to add to my filter. I also picked up Seachem Aqua Vitro Seed , and added that to the tank to give a boost to the seeding of the bacteria in the new bio-media.

    They also recommended I ease off of feeding from once a day to once every 3 days, just to keep the ammonia under control and to also avoid using my life spectrum pellets and instead use flakes for the next month or so.

    Now this morning I did another water test.

    pH: 7.4
    Ammonia: 0.10/0.25ppm
    Nitrites: 0.10/0.25ppm
    Nitrates: 30ppm

    So my pH is really fluctuating but looks like my Ammonia, Nitrites and Nitrates are consistent for the time being. I mentioned the pH fluctuation to the LFS rep yesterday as well and he said not to worry if its only few degrees fluctuation. He said as long as i can keep it staying in and around 7.0 the barbs and cycling will be okay. He said if we see it drop super low or raise super high then action will need to be taken.

    So from everything that is taking place I am wondering if my tank did not properly cycle the first time around :S or that it went through a cycle.. stalled, bacteria died off and now I have to restart over. I am also not sure what to make of the pH fluctuations.

    Thanks again!
  6. abheeshsValued MemberMember

    I would stop and step back for a bit.

    You have Eco-Complete substrate which you haven't removed or cleaned in the last 3 weeks, right? Then the substrate would have bacteria in it. Filter media has more concentration, but is NOT the only place bacteria sticks to. It will stick to decorations, live plants, sides of the tank, any surface.

    Feeding once a day should be fine as your nitrate is only 30.

    Also, one thing I noticed is, you are using RO water which means there is no minerals in there. You need minerals to buffer and stabilize the pH. Maybe add more Equilibrium?

    Let the filter run all the time. Add bacteria directly to the filter once every day for next couple days. No water changes or Prime for now. Once Ammonia and Nitrate are 0 for 2 days, do a 25% water change and celebrate!
  7. leftswerve

    leftswerveWell Known MemberMember

    Those are low readings, are you getting those with sticks or liquid tests?
  8. Racing1113Well Known MemberMember

    That's untrue. The ammonia is still available to the bacteria. Using your logic, anyone who uses Prime while cycling would never be able to cycle their tank. Prime with Stability is a highly recommended way to cycle a tank. The only time Prime is an issue with bacteria/ammonia is when cycling with TSS+ and that's only because of the way the bottled bacteria is housed.

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