I've noticed a trend. When someone replaces a mature algae scrubber screen with a new screen, or if they pitch their current scrubber and build a new one (even with different lights, flow, size, etc) that the screen tends to either mature very quickly and/or grows green very quickly. Both volume and color happen rather quickly. This is in contrast to what many consider the "normal" maturing stage of a scrubber: the screen gets covered in a brown coating - sometimes just a coloration, sometimes a slimy coating - and then eventually some green clumps start to grow, and over the course of a month or so, they get full coverage and more consistent GHA growth. I haven't quizzed many people about this, and only a small % of aquarists tend to post on forums. I also haven't considered a system that has or previously had a strong refugium to see if this is also a common effect. My thought is that when you add an Algae Scrubber to a tank that has not had any (significant) kind of macro present, that there is a phase that the tank goes through. As algae becomes a part of the overall system, there might be a shift in certain nutrients or elements which cause the screen to go through certain growth stages. Then, once the water starts to become "conditioned" to the scrubber being on the system, the GHA starts to grow. Once the GHA start growing, the tank conditioning cycle continues, the GHA grows better, etc. Eventually everything balances out to a new set-point, and the tank is now "conditioned" to an Algae Scrubber. This would explain why replacing a screen does not result in a full maturing cycle, but rather, a shortened one. Just a theory. If anyone has noticed that their screen matures quickly, or at least goes straight to GHA growth in less than 2 weeks (enough to pick off or even scrape), please post here and describe your "before" conditions Thanks Bud
Turbo I think you know my before conditions but I'll repost them here for completeness. I had a 40 gallon system with a DIY scrubber. The DIY scrubber probably only pulled maybe 0.5 cubes per day. When I migrated my system to a 55 gallon setup, I got an L2 scrubber and within a week or 2 had almost 100% algae coverage and a nice green color. When I started my first scrubber (the DIY one), I had to wait through the "conditioning" phase. So just as you state, with previous scrubbing history, new screens take off quickly.
This trend, or phenomenon is exactly what happened in my case. After running my original waterfall scrubber for a year I replaced it with a new model. The original screen first got a brown coloring, just like it was spray painted onto the white plastic screen. It then turned green before green hair algae eventually started growing. Green hair algae totally took over the screen but for the last month, before replacing the scrubber with the new model, some slimmy stuff started appearing. After running the new scrubber for a fortnight small tufts of green hair algae started to appear, randomly scattered over the surface of the screen, & eventually completely covered the entire screen. What suprised me was that no other type of algae ever grew, not even any discoloration. The screen was perfectly white until the hair algae covered it. I personally would recommend to scrubberers having trouble getting a solid coverage of emerald green hair algae growing over their screen after 4 to 6 months to either put in a new screen or at least completely scrub clean their existing screen.
That's an interesting comment - I hadn't thought of it quite this way - intentionally "rebooting" a screen after the tank has been conditioned...I'm not sure if that would work quite the same way, but I also can't think of why it would not work.
Thats essentially what I did. In the month it took the new screen to get a good coverage of hair algae NO3 & PO4 only went up slightly. I did some water changes & was careful not to over feed the tank during that period. Once the new screen got a good coverage the nutrients fell through the roof.
I want to replace the screen of my DIY ATS because the initial screen was a little bit too small for the slot I used. Reading this, would you recommend installing the new screen (roughed up) and see what happens? Before reading this I had though of hanging the new screen next to the old one for a while.
You can cut the old screen into strips and zip-tie them to the old screen, maybe 3/4" wide strips, alternating sides. I've done that, work well. Leave in place for about a month, then remove half of them, then 2 weeks later remove the rest. Or, dependent on how the growth kicks in, sooner
