Fishless Cycling Problem

@barneyadi I would do exactly as Matt suggests (just using prime to remove chlorine in the normal way) but I don't think this is a panic situation, so what is needed is just to stop it rising massively higher. The levels are rising fast, 0.52ppm yesterday to 1.28ppm today but from the water parameters you gave us the Ammonia test reading (NH3+NH4 remember) gives a toxic (NH3 only) level of 0.001ppm and the upper limit is 0.02ppm.

So this is the time to take sensible action and change enough water to drop the Ammonia back to around 0.5ppm, this will keep your cycle going but the NH3 levels (0.5ppm = 0.004ppm) will be back to safe levels for the fish with a good margin for error.
***In addition reduce the feeding to slow the daily rises and of course test and change water daily until the cycle is completed***

Incidentally I found this in a paper on NH3 toxicity levels, note it refers to 'real' toxic NH3 (free Ammonia) not TAN which is also spoken about as Ammonia.

Rough guide to toxic levels of free ammonia:
Any level above 0.02 (ppm) is considered harmful                                 
0.020 to 0.049 (ppm) is considered 'tolerated' but will cause long term harm to its growth, immune system, health, etc. especially to eggs or very young animals.
0.050 to 0.199 (ppm) is perhaps tolerated for only a few days and is very harmful.                  
0.200 to 0.499 (ppm) is perhaps tolerated for a day or two and will probably kill.                  
0.500+ (ppm) is deadly and will probably kill within a day.

I also agree with Matt.
I would do a water change of around 50%, then test the water again, to check the ammonia.
Water changes may prolong your cycle slightly, but the health of the fish is always the priority.

Do I turn filter off while I water change?

ok. done about a 55% water change and will check ammonia levels tonight. Do I need to check nitrates as well?

I agree with all of the others above re changing the water, so glad to read that you have done that.

As I think I mentioned earlier, I used both Tetra Safestart and Seachem Prime during my fish-in cycle, having also struggled with a fish-less cycle (using fish food as the ammonia source); I changed water daily, and my understanding is that the Seachem Prime detoxifies the ammonia/nitrite/nitrates for the following 24hrs rather than actually affecting the levels of them. Hope that this is reassuring.

Ok water change done and new reading taken

Ammonia 0.25
Nitrite 0
Nitrate 2.62

Thought I would be nearer 0.5 ammonia as changed 50% water but at least figures have dropped down.

So todays readings as follows

Ammonia 0.13ppm
Nitrite 0.57ppm
Nitrate 3.61ppm

Interestingly the first time I have seen nitrites, does it mean my cycle is on track?

if it continues going up should I consider another water change?

strange, just retested and got 0.03 nitrates. wonder if other reading was an anomaly?

well last night was 0.05 so would probably say the 0.03 is more correct. Will do another test after 7pm and see how it is.