I'd love to have a place to Play with MH. I have been having such a hankering to do something I think I'm just going to scratch that itch buy using an electric pump as my water source. No, it won't be practical, I'm not that silly but it will allow me to have a play and test some ideas which I have had on my mind and would really like to experiment with.
The thing I pick up from your video is Distance. Distance from the house where you want the power and distance you are piping the water.
From the vid it does not look like the house is much higher than where the generator is now. I'm wondering if you moved the generator closer to the house if the reduced frictional losses in the hoses wouldn't go some way to compensating anyway? Also wondering if it were closer to the house if you wouldn't have some pipe leftover after you shortened the run to enable you to have a 4th supply line which again would offset any deterioration in fall.
The reason I would be trying to get the generator closer to the house is that with the minimal power you have, time you run a wire back there you might be left with virtually nothing. Looks like it's a fair way and to run a wire that far with a decent gauge so you don't loose everything you are making to resistance, it seems like you are going to need to invest some money in cable.
I'm wondering if that investment would not be better spent on larger pipe again to bring the generator closer to the house to lessen the resistance fall off.
It would seem you have plenty of water but a very finite supply of generated power. I think you are going to have to watch the watts very carefully.
As far as making more power, I'm wondering it you would not do better with something like a 24V Scooter motor? These are permanent magnet and rated for 300W or more. In the playing around I have done with them, you can get good power out of the things if you can drive them hard enough. Not saying they HAVE to be driven hard but rather they would easily do say 100w If you had the capacity to turn them with sufficient torque. Maybe your fan Generator is cutting you short of all the power you could get in this setup?
The other thing is, have you experimented with Nozzles at all? Don't know what if any difference they may make in this situation but maybe they could?
I would also be going back to scratch and calculating the available power you have in the water both where the generator is now and nearer the home.
If you work out you are getting good efficiency with your present setup, well and good. If you are not, then you know where to start chasing those extra watts you are looking for.
I spose it really depends on what you are trying to achieve with this. If you just want to play tiddly winks and have a tinker and amuse yourself for the hell of it, then that's Fine. Pretty much what I want to do too.
If you are looking for something practical you want to use, then realistically you have to ask if your situation and resources aren't such that you'd be just better off getting a couple of used 250W Solar panels, sticking them on a pole, and hooking them up to a $10 fleabay controller and a battery and doing it that way.
At the end of the Day/ month/ year, that in fact may give you more power than a similar spend on the MH will give you.
Maybe something like a windmill might be viable in your area?