Horse Trailer Products Websites or look up a local horse trailer dealer in your area and ask to see a catalog.
Quality products and NO RV inflated prices for anything you need for a TV, TT, FW or LQ.
They make triangular corner water tanks that don't take up a lot of room AND they make lay down tanks for pickups too.
Look up horse trailer supplies. Horse people have a plethora of products available to them for carrying water on board in their trucks, TT's and LQ's. They will have all the different pump set ups also along with gravity feed.
18,25,39 gallon tanks etc. We do a lot of venues without water where we have to bring our own water!
https://www.valleyvet.com/c/livestock-supplies/trailering/trailer-watering.htmlhttps://www.horseloversoutlet.com/18_Gallon_Upright_Slant_Load_Water_Caddy_p/ftc-18sl.htmhttp://www.horseloversoutlet.com/25_Gallon_Slant_Load_Stand_p/ftc-slst.htmhttp://www.statelinetack.com/item/high-country-half-moon-lay-down-water-caddy/BSS10/