Thanks for the question! I trade on Coinigy and I can set a stop/limit order that is held off the exchange. You can set a stop/limit on Poloniex directly too, but I find Coinigy easier to work with as it graphically represents my order on the chart.
Just pick your sell stop, like .001 - set that as the stop value, something as the limit like .00095 and enter the order. In this example a limit order at .00095 is place on the exchange if the price falls below .001.
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