I have a shower drainage problem, there is no inspection access to the drain, i can't tip anything down there that would desolve the soap and hair particules because i have a septic tank and it would mess up the bacteria i have tried a plunger over the plug hole which gets it going for a couple of days i don't think there is a ptrap just a bend and straight out the drain plughole is a fixture to the shower tray so you can't get anything down to shift it.
we use proper drain cleaning augers for this type of problem.
as for your waste if you don't have a proper trap fitted and only a bend your install is breaking water regulations.
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