I will disagree with some of you but oh well. Sand beds are not a good/safe choice IMO/IME for a few reasons.
1) they trap waste and the goal to reduce nitrate and phosphate is to remove waste BEFORE it has a chance to break down in the water column and create these problems (BTW, this is also a problem with algae scrubbers and refugiums, trapping waste and holding it in the water)
2) in the event of a low flow situation (power outage/pump problem) a deep sand bed will eat all the oxygen in the tank very fast and then go toxic. this is why you usually only see a sand filter on large commercial systems with backup generators.
3) the bacteria that populate a sand bed will also make it necessary for you to buffer your water more to keep up with demand
my suggestion is the same as it has always been, high flow with large efficient skimming. if you use filter socks make sure to change them every day within 20 min of feeding to remove the waste. stop the nitrate issue before it has a chance to enter the cycle and become nitrate (or phosphate).