Someone asked me about my skimmerless comment in the ghetto thread via PM so I thought I'd explain my thoughts about keeping the tank clean. (Subtitle: "A post in which DWIZUM alienates half his audience").
IMHO, skimmers can do an extremely good job of keeping water in a closed system clean. By clean, I mean "free from stuff we don't want in that system." However, I also feel that they can put a huge kink in the system's natural biological balance, since they remove lots of stuff that desirable livestock (or desirable livestock's food) would love to eat. Hence, I'm hoping to avoid longterm use of a powerful skimmer on this tank.
That leaves me with a gaping hole to fill. How do I get rid of all the stuff I don't want in the tank without a skimmer? I have a three-pronged plan of attack:
1) Use of an algae turf scrubber. This is a well-proven but often overlooked method of exporting undesirable nutrients from the system - the same nutrients that can harm livestock and/or lead to outbreaks of pest algae in the display tank. My turf scrubber will be roughly based on the vertical-screen model that SantaMonica presents on various reefkeeping forums. Initially it will be lit via CFLs since they are foolproof in this application. Over time I hope to transition to LEDs, once I understand a little more clearly how to choose the proper LEDs for this purpose (some folks on a certain forum dedicated to ATSs are making real progress here, so I'm waiting until I can copy their soon to be pending successful results). I built two 1" valves into the main return line for the ATS, such that I can basically run two independent ATSs next to each other - this will allow for some redundancy and will lessen the impact of regular cleaning, since I can stagger the cleaning schedule.
2) Use of activated carbon. Not sure of the exact method I will employ here, because I'm not really sure what demand there will be at this point. I did leave an extra 1" valve on the main return line in case I want to run a reactor. I'm hoping that carbon will clean up anything undesirable that the ATS doesn't take care of.
3) Regular small water changes - I am going to implement daily changes of a few gallons a day from the saltwater storage container in the basement. This has a few advantages - it reduces the shock from larger changes, and eliminates the work of performing such large changes (which IMHO are much more of a challenge to automate). Also, it eliminates the need to heat the new saltwater, since it's entering the tank in low doses at a slow speed.
Besides nutrient export, skimming provides aeration. The ATS should take care of that, due to both the natural effects of photosynthesis and the physical aeration of the water as it's pumped over the (exposed to the air) vertical screen.
So that's the plan. We'll see how it works!
