Instruct: Classify Amazon reviews into positive or negative sentiment
Query: not warm long enough

I found that the unit doesn't keep the water warm much longer than a bucket. I filled the tub with hot water, but I didn't get the 'oooh ahhh' foot bath feeling for very long before it was over and I was headed back to the sink for more hot water.I was able to return for a partial refund and I'm trying the Brookstone unit now.