Miracle-gro Compost? will i need to add nuts to water????

during flowering stage, i put shiva shanti (18inchs) under the lights in pots filled with miracle-gro all purpose growing compost, now because im used to a flood and drain system i dont know how much water to add and if i should add flowering A and B nutes(incase of nute burn) since changing my system to pots i have a few things i need to understand. Please if anybody has any ideas that would be great

No nuts in the water..they just float.

I dont understand...have they been in the MG all the time or just during flowering?

If they've only recently been put in the MG I'd suggest taking them out and into something else - MG has quite a lot of nitrogen in it and you'll have to flush loads at the end of flowering to get rid of the taste the nitrogen will put into the buds.