Fishless Cycling Problem

The figures I use for total ammonia (ammonia and ammonium combined) and nitrite are both 0.25 ppm.
Using a caculator or table to work out the proportion of ammonia in the total ammonia, I use 0.02 as being the safe limit, though it can go up to 0.05 for a day or two.

I don't use CO2 so I don't have a figure for that.
I don't know the safe limit for phpsphate either, though that's more to do with plants and algae than fish.

Nitrate - I used to say below 100 is safe for fish but there is now evidence coming out that 20 ppm is the safe limit for nitrate. However, I need to find out is that's nitrate-N or nitrate-NO3.
UK water companies and our test kits give the reading as the amount of actual NO3. Amercian water companies give the reading as the amount of N in the NO3. Since the gram molecular weight of N is 14 and NO3 is 46, using nitrate-NO3 gives a number almost 3 times higher than using nitrate-N. This is why American forum users are shocked by our water companies having 50 ppm as the max permitted levelof nitrate while theirs is 10.  Our permitted max converts to 15 on their scale while theirs converts to 32 on ours.

And

The nitrite level should always be zero, or as close to zero as you can get it. Under certain conditions, even relatively low nitrite levels of 0.25 mg/l may be enough to weaken sensitive species. Anything above 0.1 mg/l should be viewed as unacceptable and a potential cause of stress, although some fish might tolerate very high levels.

That's better. 

Lols 

Todays scores

Ammonia 0.10
Nitrite 0.09
Nitrate 3.02

Annoyingly close to 0 ammonia and nitrite.

Also a forum member on another forum I use has said this:-

Those readings would appear as 0 on the API test since the lowest they recognize is the .25. I know you're using the new reader, it is very normal to have trace nitrites in any tank, even after cycled, though usually lower like .02-.03. You have to remember the fish constantly produce ammonia so it is always in the tank being converted over. I think it all is going really well.

I'd add in a couple more fish this week, dose prime every 48 hours or so from here on out if you see ammonia or nitrites any higher than where they're at (over .10).

What do people think of the suggestions to get more fish etc?
 

@barneyadi Hummm, I'm not sure about more fish, my inclination would be to stick with what you have and watch for a few days rather than take a decision based on a couple of readings.

You didn't mention it you are still doing daily water changes, if you were I would definitely say stick with what you have because you would be artificially lowering the pollutants and not the filter.

What is you percentage stock level compared to the community calculator? I think that this would be a help in deciding if the Ammonia input (in poop) is starting to be dealt with in any sort of volume by the filter or if the load is very small and it is still just building up without much being processed.

My first thought was to wait until at least the weekend. Not done anymore water changes since ammonia surge. Stocking level is 17% according to calculator, if I have worked it right. I have 105 litres of water which equates to 105cm of fish and I have a maximum of 18cm (4 harlequin rasboras).

But how zero should the readings be? Absolute or can they be slightly above?

Hi Sue

Is free ammonia the NH3 part?

@barneyadi Remember you are seeing levels that the colour charts can't display, the Ammonia and Nitrite charts start reading at 0.25ppm. So most people will only know they are a shade of yellow on the Ammonia scale and refer to this as zero. I think you should be able to read down to 0.05ppm ish with your kit if you are squeaky clean with your test kit method. This isn't zero but nor is it a problem, it's just your better resolution makes it visible to you.
Yes the free part is NH3 and 0.02ppm is the upper limit, I am sure you will get it well below this once the cycle is complete and you are in a good maintenance mode. This NH3 limit will translate to a higher NH3 NH4 limit that is determined by your tanks temp and pH. You know this calculation because you have done it before. The API test is reading NH3 NH4 so your 0.1ppm is not damaging the fish.
Stay on track, you are getting there

@barneyadi You could view it that way, I would be inclined see this as a partially cycled tank that is looking after the occupants of a fish-in cycle. The danger will be to get complacent and throw fish at it and have a series of unfortunate events in two or three weeks time.
If you can stay patient and let nature take its course