Sand beds and Wrasse's in a Tank

[Redfish]

I think this will be the fish of choice when we finally get the new tank, and I would like to have as many different types of them in the new tank as we can. We had a red Wrasse in our current tank, but he died when the dosing pumps dosed to much 2 part in the tank (my fault, not the pumps). He didn't bury himself in the sand at night, he would wedge himself between the back glass and a piece of live rock, this may have been because we don't have a deep sand bed in our tank. I have read, that for most of the different types of Wrasse's, they like to bury themselves in the sand bed at night. How deep of a sand bed should I put in the new tank to accommodate these fish, or will they just make do like the one that we had. I have read pros and cons, mostly cons about having a deep sand bed in a DT.

[C-21 USAF]

A DSB in a DT is a time bomb waiting to go off...a fallen powerhead, etc., could spell disaster

[Gerwin]

I am not sure you will even want a lot of wrasses in a reef tank, but they can cover in about 3/4 of a inch. Most wrasses get large eat a variety of crustaceans / snails and steal food from lps corals. NOT ALL are bad, that is not what I am saying, just do your research on each one. Deep Sand Beds are not for me and the concept behind them can be jeopardized by a wrasse digging in them to boot unless precautions are taken

[Redfish]

There are only about three or four that I really like that are reef safe, dosn't mean that they won't eat my shrimp though The reason I asked about the amount of of a sand bed that they might need is to figure out how deep of a tank that I might want to get.