This is for people who don't speak hardware-ese or have a bunch of tools......
Living in Florida, I have to replace the intex hoses a couple times a year because they can't stand up to the sun and salt air, and that's expensive. I decided the simplest solution was to find a substitute for the plastic end on the hoses, in a size and shape that standard inch and a quarter PVC could attach to. That way, I could keep the original strainer and pump etc, and only replace exactly which parts I want to.
http://i1091.photobucket.com/albums... adapter/IntexHoseEnd-picsay1_zps5c0c00e2.jpg
I spent quite a lot of time going to various hardware stores, electrical supply stores, plumbing supply stores, online, ebay, talking to manufacturers, etc. and concluded that nobody makes exactly the right part.
I started with the Carlon "reducer bushing" from home depot in the electrical aisle as suggested in this thread, but HD switched to Cantex, which doesn't work because of the octagonal shape instead of round on the end and because of the thick flange on the end. A standard "electrical box adapter" looks right but the flange on the end is too thick for the threads of the nut to catch once you add a gasket.
I ended up with a combination of plumbing and spa pieces, that don't need any cutting. (Electrical conduit is more expensive than plumbing parts.) You will need an adapter assembly for each end of each hose you are replacing, just count how many places you attach a hose and screw on a hose nut.
You will need the old nuts off intex hoses, they don't sell just the nuts.
http://i1091.photobucket.com/albums...adapter/Reused_intex_hose_nut_zps6bcdb362.jpg
For the piece that replaces the plastic part on the ends of the hose I found Dura 1.5x1.25 inch "reducer bushing" at a spa supply store, they are also available online, they are a dollar or two. This is a smooth round tube with a round flange on the outside of one end and a stopper ring on the inside of the other end.
http://i1091.photobucket.com/albums..._1_5x1_5_inch_reducer_bushing_zps08764e8f.jpg
It's made to put 1.5 inch pipe outside and 1.25 inch pipe inside, but we're going to use it backwards. If you have the tools and know-how, cut off the end with the inside ring and you're done. If not, then for each adapter assembly you need two of the reducer bushings plus a 1.5x1.5 inch "slip x slip coupler" from the plumbing section of any hardware store, they are a dollar or so. What that looks like is a smooth tube, sized so that your PVC pipe slips inside. There's a little ring inside the middle that stops the pipe from just sliding all the way through.
http://i1091.photobucket.com/albums...ter/1_5x1_5_inch_slip_coupler_zps418eac03.jpg
http://i1091.photobucket.com/albums... hose adapter/20140312_142312_zps9beeb33b.jpg
You also need hose gaskets, you can reuse the old ones that came with your pool, or get new ones from intex for a couple of dollars, or find some at a hardware store. I just reused the old ones.
http://i1091.photobucket.com/albums...ed_gasket_from_old_intex_part_zps85bd1566.jpg
*Note, if a spa supply store near you doesn't have a whole lot of the Dura reducer bushings, you can use other ones for the side facing away from the intex piece that you're attaching to. One side has to be exactly the right size and shape and thickness, but the other side can be whatever brand a hardware store has, since it's just going to have standard PVC glued into it.
Put everything together and check it first, before you glue.
First, put the gasket on the connector where the hose normally sits.
http://i1091.photobucket.com/albums...t_the_gasket_on_the_connector_zps0743f730.jpg
Second, put the Dura reducer bushing on top of the gasket with the flange pressing on the gasket.
http://i1091.photobucket.com/albums..._to_1_25_inch_reducer_bushing_zpse082b88d.jpg
Third, slip the hose nut over the bushing and screw it on, making sure it is straight and tight. The bushing should not move around once the nut is tightened.
http://i1091.photobucket.com/albums...er/Third_put_the_nut_on_tight_zps93b1aa6b.jpg
Fourth, put one end of the slip coupling onto the reducer bushing.
http://i1091.photobucket.com/albums...the_1_5x1_5_inch_slip_coupler_zps5ddb12f2.jpg
Fifth, put another reducer in the other end of the slip coupler facing the opposite direction.
http://i1091.photobucket.com/albums...1_5x1_25_inch_reducer_bushing_zpsbbe0dd34.jpg
Sixth, add 1.25 inch PVC.
http://i1091.photobucket.com/albums...inally_add_1_25_inch_pvc_pipe_zpse3824a68.jpg
Once you're happy with the layout and fit, glue the PVC pieces together using plumbing primer and glue, they usually come in a box together for five to seven dollars. **Don't glue the Dura bushing to the gasket!**
When it's set and dried, test it under pressure and look for leaks. If it leaks right at the hose nut, you might have to fiddle around with getting the gasket centered, or you might have to smooth/sand the end of the Dura bushing if it's one with raised letters.
If your pool has flexible sides, you will need at least a short piece of flex PVC at each connection that might move. Flex PVC can be glued into regular PVC fittings, that's what it's made for. You can find it at a spa or hardware store, or search online for flex PVC. It's more expensive, so to keep the cost down you could just use a couple feet right where the joints might need to move rather than everywhere.
http://i1091.photobucket.com/albums... adapter/Flexible_pvc-picsay1_zpsb2ec230c.jpg
Several helpful people have posted some amazing designs elsewhere on this site with ball valves etc. for laying out your system depending on what pieces you have, filter, skimmer, vacuum, fountain, etc etc.
) and then used the DIY rubber gasket sheet from lowes to get a water proof seal (didn't find one of those at HD).
