Codefox said:
Why would too much bacteria for the fish in the tank result in a ammonia and nitrite spike?
The live bacteria come out of the little packet warmed up and looking for food. The guidelines on the package are for a fully stocked tank. So if you use the amount of Bio-Spira to treat a 30-
gal tank because that is the size tank you have, yet you have 4 zebra danios in there alone, then all that extra bacteria will die off and become a waste product in the tank, producing ammonia. In the above case you would use enough Bio-Spira to treat, say, a 5-10 gallon tank, even though you have 30 gallons of water.
That's why it is important to use Bio-Spira for a fully stocked tank - you will have enough bacteria to support all of the fish, and not have to add them slowly while you try to build bacterial colonies, and you are not wasting this relatively expensive product.
I don't know if I am explaining it well, but the confusion about it results in disappointed aquarists, when in fact if the product had been dosed correctly for the
quantity of fish and not the quantity of water, results should be an overnight cycle, with no ammonia and no nitrite. I don't think the package instructions are clear on that, or at least they weren't the last time I used it.
If you have other tanks, however, then you already have your own colonies of bacteria, and as long as you seed the new tank with enough bacteria for the bioload you are adding, then it works overnight just like the Marineland product. I do it all of the time and don't "cycle" tanks traditionally anymore because of the seed material I have available.
Japola44 - you are on the right track with your water changes, and a very small
PWC every day might be in order. The excess debris could be causing acidification as it decays and causing a pH drop, which can be corrected with PWCs if your tap is closer to your target. Salt added to your tank will help a lot with nitrite poisoning, as will splashing of the filter return water and/or a bubble wall to help oxygenate the water. Good luck.