IME, Purigen works well on tannins. However, it makes the Purigen discolor kind of quickly. You can recharge Purigen with bleach and water, then a bunch of Prime to neutralize the bleach, but I've never done it.
IME, Purigen works well on tannins. However, it makes the Purigen discolor kind of quickly. You can recharge Purigen with bleach and water, then a bunch of Prime to neutralize the bleach, but I've never done it.