N-P-K Ratios

Hey y'all, I got a question concerning N-P-K ratios for fertilizers. I understand what the numbers mean and such, but am confused about the ratios themselves. For example, I have been looking at a few guano ferts., Jamaican bat and Mexican bat, and I have also have been looking at Peruvian Seabird. Anyway the Jamaican bat has 1-10-0 and the Peruvian Seabird has 10-10-2. The Mexican bat is 10-2-1.
So my question is, how are you able to tell what a good fert. ratio is? What would be the benefit of using these fertilizers, even mixed, compared to like a 20-20-20 fertilizer. I'm sorry if this question is confusing, it's kind of hard to explain my thought process on this one. Maybe clearer words will seek me out later and I will update. Anyway thanks for any responses.

Whatever ratio of N-P-K numbers you use, has mostly to do with what stage of growth you are in at that time.

For example, during the veg stage, the plants need a lot of Nitrogen. So a ratio about twice as high in "N" (as compared to "P" and "K") is called for, in "Veg".

On the other hand, during the flowering stage, the plants need more Phosphorous and less Nitrogen. So you switch to a flowering nute ratio that is about twice as high in "P" as it is in "N" or "K".

A good "20-20-20" will work just fine "all the way through". It's just a matter of not leaving a lot of "extra" salts in the soil that need to be flushed out later. If you just feed them what they actually need, you don't get that much of a salt build-up. That's about it!

To tell you the truth you will make it just with water (if your soil is good and has those realease nutes)
It will slower but it will be pure shit .

I'm using this to feed my young plant for the first time it has a ratio of 8-7-6 and i'm using it at 1/4 strength i'm taking no chances i'd rather grow slow and have a healthy plant than rush and destroy my babies before they have a chance.

HAPPY 420. Cant help you as far as understanding goes. IM still trying to pick things up. Just dont grow 5 diff. strains at once if you really want to fine tune anything. Get a good strain and learn on it. Learn about nutes as well this way.