Sorry for the late reply but moved over to spain and have had loads on. I fed them using the Canna range so have no experience with the bio bizz range, i fed mine every other watering using an e.c pen normally around 1.8 and also black strap molasses. My plants started to get a Ndef around about the 3-4 week of flower and started losing alot of there leaves so added Canna mono nitrogen and it seemed to slow it down. Hope you managed to get it sorted