Personally, I've gone months (up to 9 months after my first daughter was born) without a water change. The tank did suffer a bit because I have a high bioload, but it can be done. My friends Chin and TomR told me before Felicia was born that my first born would consume all my free time and energy so I had to get my tanks ready for months of minimal maintenance. GOOD ADVICE!!!! If I had to do it over again, I probably would have sold off half my fish to reduce my bioload before the baby was born.
As I tell all newbies, reefing is as much an art as it is a science. There are many ways to achieve a successful reef (especially if you're NOT doing SPS heavy). You should run away from anyone who tells you that there's only one way or the highway when it comes to reefing. After all, one person can use minimal equipment and have a thriving reef, while someone else may have all the high tech toys, computerized everything and still kill corals cause they have a "black" thumb. What works for one reefer is NO guarantee it'll work for someone else. Even something like mineral replenishment proves this point. Some reefers use automated dosers, some use 2 part, some use Calcium reactors, others use Kalkwasser, some just do regular water changes and others do none of the above, but mostly keep non-SPS corals. Yet we can all think of example tanks using each method that are thriving (and examples that are less than thriving). If I had the time and space, I would set up a fish room like TomR's and just do very regular water changes and not worry about dosing anything. However, as everyone who was here on Saturday could see, I don't have that kind of space in my home. So I have to do what works for me.
Another KISS advocate is Daniel (YVR/Carrera) always has one of the most beautiful tanks around, yet he also does it skimmerless and with almost no fish load. A couple of small fish are necessary (IMO & IME) to help "feed" the corals).
One of my first reef tanks was a KISS 35g hex seahorse tank and several friends still tell me its their favourite tank of all the ones I've ever set up. I had a HOB filter and small powerhead. Infrequent water changes. A pair of WC seahorses I trained to eat PE mysis. Lots of macro algae for biological filtration, seahorse hang-out posts, and cause prolifera & red halimeda is just pretty. It had a mat of pulsing xenia growing up the back panes and, to be honest, I still miss that tank.
The main problem is that most of us like a high bioload, so we need high powered skimmers and lots of equipment or time spent maintaining our tanks to ensure the high fish load doesn't kill our corals by reducing water quality. Low bioload allows you to get away with no skimmer and no water changes for months on end. I wouldn't recommend this for an SPS tank, but for hardy LPS and softies, it is entirely doable (as the OP's tank proves).
However, I admittedly LOVE having my big tangs & a higher than normal bioload so now I employ big skimmers (Deltec AP701 & Deltec SC 2060) on my main reef (165g with 90 wide sump) to handle the fish load. Many reefers have posted in the past about NOT using 2 skimmers on one system since they claim one will negatively affect the performance of the other. My response is that this is my tank and if it works for me, then so be it. If it didn't work, then I would pull one skimmer out and end this experiment.
Similarly, I always have a refugium with macroalgae and LR rubble in my sumps. And now, in all my tanks (fw & sw) I have either media reactors or stockings full of hydroton for biological control. Again, its what I have found over the years (decades really) to work for me and considering the number of tanks I keep and my busy schedule, reducing my maintenance times and number of water changes is critical.
We each need to find what works for us, for the time we have or what fits our level of passion (or lack thereof). If we all did what everyone else is doing, most of us would quit after a couple of years out of boredom. I think being able to find our individual way of trying to keep a thriving reef is what drives many of us addicts to stay in this addiction.
Its why I get bored with fw so quickly. Reefers, in general, seem to like a challenge and finding what works for each of us is part of that challenge.
Sorry for the essay.
