A "splash" of bleach might not be enough. Give the system a seasonal cleansing at the beginning of each camping season. I would have to go look it up but there are recommendations on the amount of bleach per gals of water to sanitize. Do a search, and then do the recommended cleansing of the system. That means filling the tanks, drawing water to each faucet location and letting it sit for 3 to 4 hours. Even 12 hours would be better. Then flush the system with fresh water.
I will tell you that here, where temps get into the 100+ water left in a system can turn black in a few days. It is not pretty.
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