Ammonia

If the level had been stable at zero, it would seem you have done something to upset the bacteria colonies. Or perhaps it wasn't totally cycled after all 

Have you done anything along the lines of cleaned the filter media, done a water change and forgotten the dechlorinator etc?


Before panicking, I suggest you enter your readings in here. You need your ammonia reading, pH and water temp. Set salinity to zero. You need the bottom figure in the right hand box, NH3 concentration. If this is below 0.05 you are OK for a day or two; if it is below 0.02 you are OK for a few weeks.
Above 0.05 now - do a water change.
Between 0.02 and 0.05, monitor the levels, use the calculator and do a water change when it goes above 0.05.
Below 0.02 keep an eye on things in case it goes up.

And keep an eye on nitrite too. If you have an ammonia spike it gets turned into nitrite.

Ammonia testers have a reputation for showing a tiny reading, usually 0.25, even when it is zero. This is particularly the case when the colour is compared to the chart under fluorescent lighting, including compact fluorescent bulbs.

With a reading of 0.0452, a 75% change will get it down below the critical 0.02 and give time for it to go up to that level rather than going to exactly .02 and having it go above that within hours.

just a thought on the 75% change new water is going to be alot colder ,is this ok

did 75% water change on sunday,tested water next day all looked good so fed fish,tested today and tests show ammonia at .5 ppm and nitrite at .25 ppm    Did a 50% water change. Not quite sure what's happening here.Am i feeding to much . Giving beta a pinch of beta flake and cp danios approx 3mini pellets for each

i use fluval aqua + water conditioner and am about 90% sure i have treated all the new water. I recently cleaned the gravel for first time in case to much waste is causing ammonia reading ,also cleaned half the filter sponge which i have cut in two.I cleaned this in tank water.

It sounds as you are using dechlorinator and cleaning the tank fine. At the beginning, the biofilm has not fully formed and the bacteria colonies can be delicate. When the tank is fully mature - 6 months after the cycle has finished - the colonies are much more robust. You can even do a small water change without dechlorinator. And the media should be treated carefully for the first 6 months.


The nitrite test in particular will stain the tube if it is not washed immediately. I always wash them straight away in cold tap water then dry them with a paper hanky. If there is any discolouration on the hanky, I wash the tube again. You could always get a small bottle brush 

There is a tendency when just starting to try to get the media into its pre-use pristine condition. It will never look like that again  Sponges need to squeezed gently rather than vigorously scrubbed, and ceramic media should be swooshed in old tank water rather than being scrunched together.
And with a new tank I suggest washing one lot of media at a time. Again, once the tank is mature you can wash more than one lot at a time. It's just those first few months until the biofilm is fully established that you need to be careful. So one biomax bag this week, the other bag next week and the one under the ornament the week after. That sort of timetable.

My small tank has just a betta and a small nerite snail which lives on the algae this tank grows. The betta gets 5 Hikari Betta Gold pellets at lunchtime and 5 at dinner time. I give him them one at a time so that I know they've all been eaten.
If I had cpds I would use flake, and give them crushed flakes, enough to cover about half a 5p coin split between 2 meals. I would crush the flakes as they are small fish with small mouths so tiny bits of flake are easier for them to eat. That's how I fed the microrasboras (Boraras species) when they were in the now sold 50 litre tank with shrimps.