I just looked at your tank specs. Just be careful that your bubble tipped anemone does not end up in the intake of the powerhead. I lost a really nice anemone to a Marineland powerhead a few years ago.
well in about a week i am planning to switch my 29 over to the 75, after everything has cycled. and i have a powerhead in the 29. i was goin to buy another one anyway too. i was also going to turn the 29 into a sump and run a big gph pump from there...so im not too worried about the water movement in the near future...
Just remember, you don't need 10x plus turnover through your sump. I put a 2200 gph return pump on my 120gal setup. Even throttled back halfway, the microbubbles were so bad the tank looked cloudy. The bubbles were pulled through the sump so fast they couldn't rise to the top and got churned through the return pump and back to the display again. Look around and see what the average gph other members are using on a tank your size. Possibly consider a closed loop system for added flow.
Since youre upgrading, you may want to consider a CLS for added flow.tat2d was on the money about too much flow through the sump. No sense in running more through it than the skimmer will process and if the velocity is too high youll have big time bubbles. Do a search on sumps and see what folks have done.
For the CLS you can drill the tank or do an over the back desing. I personally prefer the drilled route. Its not as bad or scary as it may seem. You can drill it yourself or some LFS's will do it for you, even a glass shop or to may do it. For the design, simple is best and the CLS is the most effective way to add flow to the tank and get the most out of it from a utility stand point. Flow can really aid in keeping the tank clean. You only need one pump, there will be no electrical current in the tank and no power heads taking up space or infringing on the view of the tank!