Help (new): Pressure washing from water tank options -

Newbie Questions
1

We have a 250gal water tank on a trailer, 150ft of hose, and tried a 3500, and a 2900psi pressure washer machine and the gravity feed was only good for a minute or two then dropped out to no pressure. We assume the length of hose reduced the amount of available pressure significantly, combined with the low height of the water tank, meaning not enough incoming pressure. (duh) but really learning…
For context, 3 tennis courts exterior concrete only, and we couldn’t move the water tank around, stuck on one place.
Questions…
a) If we ran the pressure washing unit at the source of water, and leveraged an extended pressure washing hose from the unit, to the nozzle head, would that have solved the issue?
note:
We did put a small water pump in between the two 75ft hoses, but that didn’t improve it to any real degree.

b)Would a larger pump be the solution, if we put it at the source of water?
Any suggestions?

Note: I’m still searching sites for the same issue and found this
Water pressure can decrease for every 100 ft (30.5 m) of distance due to the gravitational pull and resistance within the pipes . A general rule of thumb is that the water pressure drops by 0.433 psi for every foot of pipe, so for every 100 feet, it would drop by approximately 43.3 PSI (3 bar)

2

Direct drive machines don’t like to be gravity fed. They need at least 50psi to operate properly without cavitating the pump. This is why you will find belt and gear drives on professional outfits using a supply/buffer tank.

If you can’t get a hold of a belt drive, you’ll need to add a fairly high GPM electric pump after the water tank.

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3

I think he’s trying to run a garden hose between a tank and a portable machine

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4

I get that as well, so he’ll need a booster pump in between.

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5

Hey guys, both are correct, we had a 75ft hose, and a small pump in between, but it clearly wasn’t enough. Appreciate the support, answers, and non-judgement (already frustrated with myself) … I’m looking at if we can rent a water truck with some sort of pressure system at the source. I think the costs are nuts but still my avenue to follow through on this work.
Any thoughts on that approach? Or should we look at sorting out a high GPM electric pump?

6

Why wouldn’t you just buy more PW hose

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