They are absolute junk, I have at least 4 non working 526gph models in boxes in my garage.. not one of them lasted more than a year... the first died after 27 days, the other 3 followed soon after. The company repeated dodged my emails and calls, then when I finally got someone to approve the RMA they wanted me to pay to ship it to them and to pre-pay shipping and handling to send it back.. It is also worth mentioning that the 500+ gph unit only moves about 1/2 the amount of water it claims. They are cheap, flimsy crap.. there is a reason they change the name every year and sell them under another brand...... just my 2 cents.