Custom designed pool theater system

I’d like to start with “I am not a audio guy, but I am a designer of things I can’t buy”. That being said a few years ago I put in an inground swimming pool. This year we started watching movies on a projector at the pool. My kids love it. At first I used just a sound bar but the sound was horrible. So I upgraded to a small amp and two speakers that I would bring out just for the movie. This worked well but I wanted something permanent. 
This brings me to where I am now. I have 4 speakers that I bought off of Amazon (I think they are 4ohm) and a Pyle amp paired with a marine grade Pyle head unit. I build a custom pool box to house my power supply amplifier and head unit. I ran the speaker wire around the pool area thru the vinyl fence. The firs test run is right around 200’ and the shortest is 10’. The two furthest speakers produce little to no sound. I have the closest speakers on one channel and the furthest speakers on the other channel. No matter what I do (ie larger wire or adjusting the channel power) I can not get good quality sound out of the frustration two speakers. 
So my question would be what can I do to solve the problem? Switch to active speakers instead of passive? Or I have seen on here where wires are ran in pairs instead of one large wire. 
I am new to this forum. If it’s possible to post pictures I can share some of my set up. 
Thank you ahead of time for any help that you may give