Andy M Fishless Cycle

I agree that a pH drop is unlikely with hard water but theoretically it is possible.

Something you could try - I did frequent water changes once I was getting nitrite. I freely admit that huge water changes in a 25 litre tank are easy, and they would be time consuming in a larger tank. But you could try a biggish water change, say 50%, and see if that helps. If nothing else, you'll get practice using a siphon tube before you have any fish in there 

If you don't fancy the water change, add some more ammonia at your usual time and see what happens tomorrow. If you still have the 'dose amount plus 0.5' tomorrow, you'll know something has happened to your ammonia eaters.
It is possible the high nitrite is affecting things.

Based on your Nitrate (which I assume is the same as your original test), I would definitely go for a partial water change as Sue suggests. It can't hurt.  However, if the Nitrate has moved up from your original testing, then you must begin water changes to keep the levels under control.  Sue experienced the stall, and it was indeed odd, despite having good pH.  Mine crashed the pH because I'm in a very soft water area so very little buffering available.

Sorry 

Your ammonia is 0.5 at the moment. If you add you usual dose at the usual time, you'll then have however many ppm you add plus the 0.5ppm you have at the moment, ie dose amount plus 0.5.
If it is still reading that 24 hours after adding this dose of ammonia, it means that none has been eaten. You were seeing the ammonia level drop after adding a dose so if there is no drop tomorrow, something is interferring with your ammonia eaters. But if it does drop lower than the ppm you add plus the 0.5 already there you'll know your ammonia eaters are fine.

Adding a dose of ammonia today will show whether or not your ammonia eaters are still working. If it turns out they are not, we'll have to try and decide what to do. With a pH of 8.2 you have ruled out a pH crash. Your nitrAte is not particularly high, but your nitrIte might well be. All you know about that is that it's somewhere above 5. Another test you could try is add about 1ml of tank water to the test tube and top up to the line with tap water, then test for nitrite. Since the tube holds 5ml to the line, add water to a fifth of the way up to the line. If the reading is then somewhere on the chart, multiply by 5 to get the tank reading. If it's still at the highest colour, then your tank has at least 25ppm nitrite.

If it does turn out that you have a very high nitrite, that could be inhibiting the ammonia eaters (although it usually only affects the nitrite eaters). A water change would get the nitrite level down.

That does sound very odd. 0.25 should equate to a tank nitrite of 1.25 which is well down the colour chart 


Grasping at straws time -
Are you washing the tubes very well after use, then drying them? I use a paper hanky twisted round till it is the right shape to fit in the tube.
How are you transferring the water from the tank to the tube? I use a pipette which I rinse well afterwards. I have recently heard that some people dip the tube into the tank and scoop the water into it - it never occurred to me to do that, probably as a result of having studied chemistry at university.
How are you getting the reagents into the tube? Holding the bottles vertically above the the tube or at an angle?
You are using both ammonia bottles for the ammonia test and just the one nitrite bottle for the nitrite test?

washing tubes and drying with kitchen towel,  holding bottles vertically, using a 5 ml syringe to get water, just topping up after a 50% water change,

Enjoyed using syphon 

Oh and added 10ml of nutrafin aquaplus yeah?

So water changed, my next step is?

Post 50% water change

Ammonia 0.25

Nitrite  Maybe somewhere between 2 and 5.   So hard to tell difference in the two shades

So I will dose my 0.5ml later?

Thanks for your help Sue. Was starting to lose all interest

Day 10

Ammonia 0.25 ppm

Nitrite either between 2 and 5 or above 5 ppm