Well, for now I just use Miracle Grow powdered fertilizer. I add it to a plastic jug, then add water, and shake it up well.

The nutrient ratio listed on the box is: 24-08-16.

I use LESS than the recommended amount on the box, per water amount. So I make it more dilute.

However, one VERY IMPORTANT tip I learnt about using fertilizer is to FIRST add just pure water.

NEXT, add the fertilizer/water mix.

This helps prevent fertilize-burning effects.

I guess... to use a metaphor, it's like when you want to add bleach to a load of laundry. If you put your clothes in, and add bleach while your clothing is dry, it will "burn" and stain them. But if you add water first, then bleach, then clothes, that prevents burning.

I do however still have some brown tips on the leaves, but not too bad. In my case however I suspect the few brown tips might be due to lack of humidity in the room now that it's wintery and I'm running the heater.