How often should I water my Lophophora Williamsii?

How often should I water my Lophophora Williamsii? Between two watering, but constantly check to ensure that the soil is dry. Throughout the winter to keep the cactus from drying out altogether. 4-7-7 or even 2-7-7 would suffice. Because the roots must reach for water, this ensures robust roots. Lophophora Williamsii, “William’s elephant ear cactus”,…