Shipping Fish via USPS

no it wouldn't. They don't offer a guarantee for live things within a box, they cover the shape of the box. USPS does not guarantee live things, period.
 
i have had the most reliable luck with usps. Despite a handful of lost or damaged packages, the best results for me have come from the good ole usps.
 
I use USPS for most of my shipping too, occaisonally UPS depending on the destination. Regular UPS Ground service delivers the following day to a good-size area, while Priority Mail would take 2-3 days simply because the shipment is routed differently. I'd estimate around 95-96% of my shipments, both coming and going, have been fine. There have been a few incidents of lost or damaged packages, but no shipping service is perfect.
 
My very first time having fish shipped to me was a box full of MTS that arrived dented, crushed, and soaked in what was very apparently the water from inside the package. Luckily some of the snails were smart enough to hang out in the corner of the deflated bag and get enough moisture that I had about a dozen survivors out of a hundred. I've had much better luck since then, until my future baby plecos were tossed around like a shake weight.
 
Just don't tell them what's inside.

I package all my plants/fish/shrimp well and send them on their way. When they as if theres liquid or living things inside I say no and they say ok. I don't label the boxes fragile or liquid cuz they don't care. In fact I get more boxes that are roughed up when they have those labels on them.
 
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