I tried ice bottles, they went under my waterfalls and started to flood my room. I saw a 750gph dc pump for like 80 bucks, would have to look around. Need something decent and if your like me, more then I need. The pressure will be factored by the manifold a lot. You just need to break surface tension, like push bubbles 2-3” into the water. I haven’t played enough with anything but my system. Typically ideal from what I see is running a 1” feed and a 3/4” manifold then reduce to 1/2” for the nozzle to the buckets. Or just run 1/2” the whole way. I guess design depends if you do pvc or barb hose too. Both work the same.