To my knowledge, most of the small ones (with a 0,5-1L) tank don't usually get a full 4x4 tent down to the desired level you want.
My tip is to get a bigger dehumidifier with both a hygrometer (with at least 40-50-60-70% as steps to put in) or 35-85% if possible.
And to have one with different positions/levels you can put in, mostly that is fan related, so low/medium/high/very high and this also changes the power draw (get one from 100 to max 300-400watt). A tent/or room in full bloom with maximum water givings and transpiration levels need quite some capacity to dehumidify to 40-50%, probably one with with about 0,5l-1L water per hour. Either choose one where you can put a hose on it so you can fill up a tank with the water, or take one with at least a 4-5L water reservoir in the machine. So it can run at least half a day at full power without emptying the tank. Trotec is a brand that I can recommend for that.