How hard Is it to have a 10 gallon clownfish tank?

[Nemodao]

I currently have a 10 gallon planted aquarium with 2 filters. The cheap one that you would find in a kit and a tetra whisper. I also a heater. My substrate is Flourish(which is a sand for plants. I have 3 mollies. I want to switch to a FOWLR tank with just a clownfish and a fire fish and a clean up crew. Is this a bad idea, is it very difficult? I had a 55 gallon FOWLR at my old house in Wisconsin but I had to move so we sold it. What else do I need other than a hydrometer,salt, protein skimmer, live rock and food. Can I use my substrate or do I have to buy sand made specifically for saltwater. Do I need a reverse osmosis unit? Or can I just use conditioned tap water? Tds levels in Toronto is low but not 0. Or should I just buy premixed saltwater from my local petshop for $1 per gallon?

 

[TheTodd]

I would not put a Clown in anything less than a 20g.

With a 10-20g, I would not run a skimmer. If you did frequent enough water changes, you should be able to keep parameters in check that way.

For a small tank, I would probably just buy from the LFS if it was only $1 a gallon. Less work, IMO. If you decide to mix your own, I would use at least RO. Tap can be questionable, as there could be things in it that you can't test for.

Small tanks can fluctuate quickly, so I would not say that they are "hard", you just have to keep a closer eye on them.