Surprisingly the way I have it set up, the only time I put into it is a 30 minute water change twice a month. It doesn't allow me to keep the crazy corals and have incredible growth but I enjoy it more that way. I might try the more advanced version one day but for now, time is of the essence.
Back when I had one I was leaving on SCUBA trips frequently, It was a lot to ask friends and family to look after it and it always seemed to crash while I was away. Glad you have yours worked out to a manageable system.
I loved keeping fish. I used to be into fresh water tropicals. Then once I got more advanced I started setting up tanks with fish all from the same river and region. Almost all Characidae family, even some piranha at one point, but what I really loved was large schools of small fish. Cardinal tetras were one of my favorites. I had 4 tanks going at the same time, miniature ecosystems.
Now I just keep a single Betta Splendens, but my last one died after about 4 years. Haven't got another one yet so my tank is sitting vacant currently.