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this, just adding ammonia and hoping for the best is a recipe for disaster - I appreciate that 2yo kids don't have the appreciation of what it takes, but this something where you need to be a strong mum, the cycling process takes time. What you need to do now, is to replace about 1 3/4 gallons of the water with fresh, to get the ammonia level down to something that is about right - I reckon your ammonia level is about 8ppm, it needs to be around 3ppm.
A 2½G tank is way, way, way too small for 3 neon tetras - they are active fish which need room to stretch their legs, er, fins. Yes, they will fit into the tank, and a great dane will fit into an average bathroom too, but no responsible pet owner would suggest it will be fine in there permanently.
May I respectfully suggest that you invest in a Betta, often referred to as a Siamese Fighting Fish (or just plain Fighter) here in the UK. A single male will be happy as a pig in the proverbial in a small tank, and you can let Matthew choose his favourite from the range in the shop - most shops have a variety of colourations available.
. I changed the water, about 1 3/4 gallon of it but the ammonia still reads 6ppm after 3 hours. Should I do a greater water change? Perhaps take out the fake plants? Or maybe start the cycle all over?
