How Deep Should The Substrate Be?

[Rob5]

I have decided that in the future i will be converting  my 200l tropical and turning it into a FOWLR.
 
I have been reading up on setting up a marine tank and have read many different opinions on how deep the substrate should be. 4" deep pops up most regularly
 
My tank is approximately 20" high and having 4" of substrate seems to be quite a lot.
 
I will obviously be having a CUC so want to get the depth right.
 
Argonite sand seems to be the most popular to use but would I be able to use another substrate that would be cheaper or is Aragonite the way to go?
 
Any comments on the above will be greatly appreciated.
 

 

[RRaquariums]

Unless you intend on keeping a type of fish that requires a deep sand bed for burrowing there isn't any reason you can't go with a depth of 2 inches that's what I personaly went with in my tanks and it seems to be a good depth. Its a bit of money but in the long run aragonite sand is the way to go it helps buffer ph and is fantastic looking IMO. Anyways that's my two cents worh hope it helps.
Good luck

 

[Rob5]

Thanks for that Matt, most appreciated

 

[RRaquariums]

No problem asking lots of questions is how we succed at this hobby.