You had better hope you do find something wrong with the hose cause
it's cheap and an easy fix.

If it isn't your hose then either something is pressurising your
cooling system beyond it's ability to cope (blown head gasket) or there
is a incipient failure elsewhere that is holding under pressure, but
when your system cools it is letting in air rather than sucking water
back.

If the later, the possibilities are endless, but the usual suspects are
hoses, thermostat housing, radiator, pump shaft, welsh plugs - in about
that order.

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Is the hose in the overflow tank long enough to reach the liquid level?
I woulnd worry to much about it, have you tested the flow? Removed the cap
while the cars warm (not to hot) and running? If alls okay dont fix it.