Hey just had a thought (which is rare for me) The 530 is rated at around 50 watts how much more would that add to your monthly bill say compared to a AC110? I could look up the 110's but I'm not sure how to brake down monthly cost. And second would say a 530 do that much better then the 110 bottom line?
Assuming you pay $.010 per KWHr, running the Marineland 530 (which I believe uses 56 watts) would add about $4.00 to your monthly electric bill.
An Aquaclear 110 uses 14 watts, so that would add about $1.00 per month to your monthly electric bill.
The formula I use to determine the cost to run a piece of equipment is as follows: [(Watts/1000) x 24hrs x 30 days] x Cost per KWHr.
In the case of the 530, that's [(56/1000) x 24 x 30] x .10 = $4.03