I used coconut soil, which I bought in gardening shop - pure and as and addition for fertilizing. It was perfect. But I'm not sure that "coconut coir" and "coconut soil" are the same.

Suggest you check with the folk on the Hydroponics forum as this system is often used for soilless growing. (Coir and perlite.)

yes, as stated above you'll need hydroponic nutrients. i sugest www.wormsway.com as a place to look. they have knowledgable people who can guid you toward a fertalizer that will work for what you need.

good luck and happy growing.