I'm terribly new at this and have no idea what I'm doing so please do bear with me.
When I tried it on a sprinkler using a 12mm hose, the pressure is a fraction of what I normally get. This is currently how I have set it up. (which I have a feeling is the problem)
I replaced the connector that points upwards (see original photo from link) and replaced it with a 32mm to 20mm reducer (A) so I can fit my hose (B) which is ~10m long.
Any suggestions/thoughts on what I should be doing whether having a more powerful pump or correctly configuring the connectors and pipes etc?
I would highly appreciate the physics side of it as well so I can apply this knowledge elsewhere.