In a big rez like that, I would use a dual outlet airpump with 2-14" bars from Wally's...Total cost for lots'o'bubbles...
20-25 bucks...

My hydro store has these 2, 3, or 4 foot flexible air diffuser's
they are new on the market I bought 3 or 4 for around $5 bucks apiece.

I have not found the need to buy any high dollar airpumps yet. All mine from Wally's, no problems, still use the 1st one I bought. lw