New to the game would like some advice and some ideas

So lets get straight into it.
Im using a water system that is gravity fed too three outdoor plants that are growing in a hiding spot. These plants are doing quite well but ive noticed some difference between them. They are different varieties two of them are big two pounders and one is a auto flowering one. The auto flowering one is growing really well looks amazing and really is going as well as i hoped. the other two on the other hand are struggling and i dont seem to know why, they are all getting the same amount of water and the two pounders are getting more sunlight then the auto flowering one. I just dont seem to get it? Are the two pounders getting to much sunlight?

Also what do you guys think of compost? Im think about putting a compost system in to help my plants even more. Currently they are all in pots(Just about to move the auto flowering one into the ground) im going to use water crystals to help the water last even longer!

My automatic gravity fed water system is doing pretty well i believe but its hard to get water to it. Because i have to walk the water long distances. Do you think river water that isnt flowing would be appropriate to use?

Also im just using a normal bug spray that you would use on tomatoes its nice and organic would you recommend anything else? im using a water based fertilizer that is also meant for tomatoes

Bump, Someone please reply.

You think the two pounders pots could be getting too hot? What exactly do you mean by a compost system? I would refrain from using stagnate water. Before using any pesticide google the active chemicals...I use just use neem oil in veg and azamax in bloom, also i think it's a good idea to stop well before harvest.Are you feeding the plants?

also images help with sad plants.

Yeah pots did get are getting hot man, cheers for the reply uhm ill upload images soon going out there soon