too much curent?too little current?

[cjm033]

tday i fund a small pump for one of those things that come with those little rock fountian things (the foundtians are usually smooth round rocks and arent really big about no bigger than 1ft diameter and 8 inches high) but anyway i took the pump from one of my moms old ones that didnt work and decided that i would try to fix it well it worked i took it apart and fixed it within 10 minuites and cleaned it by the size it looked like it would be a great powerheaqd for my 2.5 gallon due to it only being 1.5 inches wide and 2 inches tall and having a almost double screen over the input so nothing could get sucked into it iit has a thing to adjust the output but i was wandering if this and my whisper power filter (5-15 gallon design) would be too much current for my tank i have the "powerhead" currently running in my tank on the lowest output it has is that too much curent?i dont see excessive bubbles so i assuming its not but i was just being sure. i am also moving in a few days and was wandering after i move im gettn lr (i cycled my tank with ls) if just the "powehead" on the highest output would be enough current w/o the filter for my tank? (because personally i dont like the look of a big tube comming down form the middle of my tank and it tankes up alot of room) input would be greatly appreciated,Chris