not trying to point out the obvious but 10' over 250' will create a shitload of backpressure on the line, due to the weight of the water. you will need a powerful submerged sump pump and a smaller outflow pipe to reduce the weight of the water. a chack valve would not be a bad idea. lets pretend you used 1" poly line. a 250' run of 1" line would hold 10.201 gal of water, which would weigh 85.18lbs. its take a decent pump to move that much water... and a decent pump means a reliable power source. you might look into a 'whisper' generator which is made by honda, there very very quiet and would give you the power you need to run a pump. but remember this- if your worried about helios... a straight pipe running from a water source to a patch will like like a straight arrow pointing to your grow to the IR cam.... and the generator though quiet will look like a red hot peice of satans shit with a glowing exhaust trail to the IR cam as well.