I don't think is light issue.....alaska gets solid daylight& allows them an actual
growing season.leaf browning tells me water issue.not sure how they treat that kind of water.when i've had bad water to water with I've used distilled water.rain water is great if you get rain
might check the soil also your soil could me murcky stuff when wet and maybe holdeing water too long.you could change soil out and just repot in same pot& may help watering.I just don't know about them drinking waters.I drink some sometimes when out & couldn't even tell you the name but that it has a reddish lable and maybe the word "
spring" my water comes from a natural
spring fed lake& my waterman lives out here& lets me know when water inspectors are comeing cause he ups the chlorine& he flushes the lines regularly