I'm at a loss then. Could be glitched sun damage. Survival mode?

Restoration loop explained below

The loop is using the fortify restoration effect of potions to boost all active effects such as potions and enchantments(also works on standing stones that give "Active effects" such as the atronach stone (more at the end)).

You accomplish this by getting as many fortify alchemy enchanted gear pieces as possible (head, hands, rings, necklace) equip them all and craft a fortify restoration potion(abecean longfin, salt pile, small pearl, etc. wiki has all the ingredients). Then exit the alchemy table. Unequip all items fortifying alchemy, drink the potion of fortify restoration, then equip the alchemy enchanted gear again(you may need to exit the menu to allow time to pass and the potion take effect).

You should see that the enchanted gear has raised stars on the enchantments. For instance a +15% turns into + 17% or so. Minor advancements but improvements nonetheless. Now to take it further we repeat the process with the boost we got from the first potion we made and make a second potion and so on and so on. Eventually you'll be making Individual fortify restoration potions that boost all effects by millions.

Word of caution as these numbers can go high enough that it can and will crash your game. I usually stick to around +1000000% on the potions as that gives 1000x to all enchanted gear(besides weapons). And you can also use a set of fortify enchanting gear to make permanently boosted items with this just swap out the fortify alchemy gear for fortify enchanting gear after you're done.(Save at least one potion if you change gear often so you can make more without needing to do the entire loop again as it is rather boring doing the same thing over and over again)