I have been growing weed for 20 years off and on. Back in the day I used Hydro, Canna A+B and PK 13/14, then I went to organics. It was a few bags of Bio-Bizz All Mix, then loads of Grow, Bloom and Top Max. Cost a fortune.
Then I had kids and couldn't afford all the fancy pants nutes, so I went over to buying cheap compost adding chicken manure and some sulphate of potash. It worked fine.
These days I am too old and can't be arsed with all the hype surrounding nutes and grow mediums. They are mostly snake oil IMHO. All the plant sees is NPK and some essential minerals. These days my seeds are germinated in Jiffy plugs. I then put them in some GroSure potting mix, for the first 5 - 6 weeks and just add water as needed. GroSure Potting Mix is not the cheapest and isn't the most expensive. It is a Peat based compost mixed with Coir and Vermiculite.
At week 5 - 6 I pot them up into Jack's Magic Compost Mix, which is a compost and peat mix with added calcified seaweed to which I add Vermiculite and Mycorrhizal granules. Then I veg them for another 4 weeks and continue just adding water. I will then pot them up into their final pot. I add more Jack's Magic and Vermiculite. I give them a few more days of veg and flip them to flower. Then at week 5 of flower I simply give them Tomorite Tomato Feed NPK 4-3-8 at 50% of the recommended dosage until the end.
It is a cheap and effective system. I get consistent results. I am also not filling the planet up with hundreds of little plastic fertiliser bottles. I'm in the UK. A big bag of GroSure costs me £5 and is enough to do 24 plants. Jack's Magic is £12 for 100L. Vermiculite is so cheap for a massive bag I hardly notice the cost and a bottle of Tomorite is £3.99 and lasts me at least a year.
Everything I use is from the local garden centre and is the same stuff your Mum uses on her Tomatoes so is 100% safe to consume.