A 1000w light and its ventilation system should run off their own 20a breaker; you can run some pumps and minor shit off it too but that is a big load.
Get the TV and computer onto another breaker entirely. Also, remember that the breakers in most bedrooms are not even rated for 20a; 15a is more common, and the wires in the walls will be, at best, a 14 gauge Romex, when a 1000HPS really should run off 12 gauge especially if you are also plugging in fans on the same run.

Your setup is not safe. Split it. Go down into the cellar and look at teh breaker box. If there is one designated 'laundry', that is a good choice for a big light. Also 'oven' (obviously don't run the oven when lights are on) or 'garage'. Those are virtually always wired up on 20a dedicated breakers.

If I were you, I'd get my stuff out of the bedroom and into a room likely to have better wiring. At the VERY least, put the TV and computer in the living room on a different circuit.