cerianthus said:55G FO tank.OK. Any thoughts on how you would decorate the tank (Rocks??) I was thinking fake corals or dead corals
W/O LR, that means you tank has to have other means of Bio Filtration. Correct thus FO no LR.
Best bet will be W/D Filter or DIY Sump w/ filter media. Would either one of these be a must in a FO tank? Do remember that any kind of filters you hook up requires constant maintenance to make sure things don't build up to produce nitrate.
Can be done and have done with Undergravel filters+Canisters w/ Crushed Corals and most importantly a Protein Skimmer. This was when other options were NOT available/too expensive (early 80's/mid 80's). Simple set up w/ Hardier fish such as grouper, Trigger, Eels can be kept w/ routine maintenance, was able to keep running. I am not saying to use UGF and Canisters. Like I said, W/D or DIY sump is better option than UGF method.
But My question to you is Why not Live Rock? I wanted to do FO, mainly for asthetics. I do not like the look of the rock. You don't have to fill the tank w/ LR. Investing in LR will be the best decision you can make on S/W. Although can use other rocks such as Lava Rock which will also be bio active given time but does require regular cleaning since will trap detritus in bigger pores. If willing to spend money on Dead Rocks, please consider spending that money on LR ,whatever amt it may be. Better than nothing. By having live rock I understand that will help with filtration, there are no other means of filtration w/o using LR (For example penguin bio filters). Other wise I would be setting up a FOWLR tank and not a FO tank?
I can go on but reconsider the benefitS of LR