Fish blood and bone (about 8 tablespoons per 20l/5gal) - Down to Earth All Purpose is a good option
Quality organic compost
Vermiculite (15% of mix)
Perlite (25% of mix)
Kelp meal (4 tablespoons per 20l/5gal) - if you can't easily get this organic liquid seaweed fertiliser works just as well
Mycorrhizae (add to planting hole so it contacts roots when transplanting or bury in soil near to where the plants roots will be)
Dolomite lime (10 tablespoons per 20l/5gal)
Other useful ingredients are vermicompost/worm castings, coco (10-20%) and biochar (10%). There are lots of other things you can add to further improve your soil such as rock dust (gypsum/basalt), shell meal, alfalfa meal etc. I'd recommend having a good read of the soil mixes in the organic grow faq section to get a good feel for the common ingredients but the above list will give you excellent results.
For the Mycorrhizae addition you could use a product like this
If you did go down this route then you would need to reduce the amount of Down to Earth/FBB you add to around 2-3 table spoons per pot to avoid over cooking it.
With organic soil growing you don't need a ph meter or to measure your ph, the dolomite lime helps prevent the ph dropping too low (caused by the FBB), helping to keep it between 6 and 7, also the mycorrhizae act as a buffer making the nutrients available to the plant at a wide ph range so as long as you have a healthy soil with not too much fbb, a good amount of lime and mycorrhizae nature will do all of the ph'g for you so all you have to do is add water (that's been sat out overnight) until harvest.
The beauty of this method of soil growing is that once you've built your soil it will give amazing results year in year out with the only maintenance being the odd top dress of fbb to recharge the soil every few runs