Plastic jugs for water storage?

Hi all, I'm having Finn "betta-sat" for about 10 days with family members, and I'm trying to find a way to make water changes easier for them. He'll be in a 1.5 g tank for the duration of his stay with them, so I'd like for them to change his tank once every other day or once every third day. He's used to the water changes frequently, so I'm not worried about that stressing his body out (he's in a small tank for now while I'm undergoing a fishless cycle in his soon-to-be larger home!). Anyway, my question to you folks: Will it be okay for him if I keep his tap water + conditioner + his normal (and small) dose of aquarium salt in plastic water jugs? I guess I'm mostly worried the plastic would leech into the water or something like that. Hopefully not. Thanks!!