I have done Zulrah few times and I can tell you that most people die by the venom clouds, so you are not alone at that. Zulrah requires longer attention span on all the mechanics for a short period of time. Stats under 85 aren't recommend for Zulrah IMO. If you generally are a bad flicker I would recommend 90+ in ever combat stats. Don't waste your time. Get your combat stats up and try again. Once you have the appropriate stats, get to know the rotations by watching YT clips - there are lots of them around. I suppose you use the vital items required for the fight too, right? - e.g recoil ring, Trident of the Swamp. Likewise Jad, don't get nervous when the boss do too much dmg or when you're close to kill it.