I have a 90 g and I run a canister EHEIM works great, also have done the DIY top off in my tank, works great, now saying that what I wouldent do for a SUMP. IMO and what I have learned over the past little while I would never use a canister again exsept in a hospital tank. You can make a basic sump out of a used tank or anything for that matter the sump for my future tank is 100g water trough from UFA 100$$$ . well thats my 2 cents.....
Richard