I grow my Mexican pinguicula as houseplants. Usually, they do really well and thrive under my conditions. However, this year I have had a few losses to browning heart disease. My soil mix is peat/silica sand/dolomitic lime added. The ratio of peat/sand is ~40/60 with 1/2 tbsp of dolomitic lime per 2 cups of mix. I am thinking about changing to a lighter mix, but I worry it may be too dry for houseplant conditions. Does anyone have experience in growing pings as houseplants and having a very light and airy soil mix? If so, what are your mixes? Would a 20/80 peat/rock-based mix be too dry?