I have been fighting Cyno for about 2 months. My system is 2 years old, but it is a broodstock system, and I feed 5 times a day. I added a waterfall scrubber about a year ago and I have no algae problems, but cannot get rid of cyno. Most of the advice I see says reduce nutrients. How????? I thought the ATS would also help with cyno, but not so far. What have others seen or done?
Cyano is usually the last thing to go, if it's a persistent problem, then tweaking the scrubber might be in order, as well as using another method in conjunction with the scrubber. Before giving advice, I like to collect info about the system: Total water volume? Other filtration? Nitrates? Phosphates? Scrubber screen size? Lighting type/size/etc? Scrubber lighting photoperiod? Method of water delivery (pump, overflow, etc)? How often do you clean the screen? About how much algae do you collect with each cleaning? Pic of tank, pics of scrubber, etc - as many pics as you want...they really can help
You sound like my doctor, should I bend over? Just gathering this information is more work than your help may justify! Total water volume? 350 gal Other filtration? Skimmer Nitrates? 0.0 Phosphates? 0.0 Scrubber screen size? 9 x12 Lighting type/size/etc? Double sided 35 watts led each side. Usually run at a bout 30% intensity. Scrubber lighting photoperiod? 12 hours Method of water delivery (pump, overflow, etc)? System pump. How often do you clean the screen? About how much algae do you collect with each cleaning?
Hey Windy Same as from R2R I assume? If so then I know you have a lot of experience with scrubbers. I haven't ever ran a broodstock system myself so I'm guessing that there are some unique characteristics, depending on what you are breeding. Such as, bare bottom, lighting type/period, etc. Also I'm guessing that you're feeding something like live rotifers? Cyano has to get its nutrients/fuel from somewhere, so where is it growing? Rock, sand, shelter items (pipe sections, flower pots, etc). Or is it just right on the bare glass? Or on sponge filters? What I've seen is that if you have a pretty clean system and cyano is just hanging around, then you need to bump up the strength of the scrubber. What I've found is that as long as you have a nice mature screen that consistently grows well (which is why I asked about cleaning frequency and amount collected) then you can increase the photoperiod and intensity, sometimes quite a bit. As an example, I've mentioned this here, I have a 120 with a 4x6 screen (L2) and i had this on 12/12 photoperiod for a long time (about 2 years) and had been cleaning every 10-12 days. Then I accidentally flipped the timer switch to "outlet on". I caught it about 5 days later when I had enough to clean again. So I have left it on, 24/7, for a few months now and I keep growing algae, nitrates and phosphates are still very low (N=0, P<0.04) and I keep growing algae with the LEDs running full out (6 reds at 100% and 2 violets at 50% on each side). So that's 18W of red and equivalent of 3W of violet per side (total 21W) on a 24 sq in screen. But if you look at actual power consumption, a 3W DR only consumes about 1.7W (2.2V * 700mA = 1.68W) so actual power we're talking maybe 12W per side. If you're running 35W on a 9x12 screen (which is 4.5 times the size of my example), and your 35W is based on actual maximum power consumed (that is, 1.68W per Deep Red, if they were ran at 700mA), and you're running them at 30%, you should be able to bump up the intensity and get some more production. You also have a pretty large water volume, so increasing the intensity and/or photoperiod should give you more production without causing a reversal in growth - but watch for that. You're running in low nutrients, but with a broodstock system, I'm also guessing that you have a lot of eating/waste going on, lots of little fish producing little amounts of waste, so you have a rather constant waste stream. Also, do you have really low flow rates in some of the tank, especially the new fry tanks? Is this where the cyano is worst? If so, this might be tough. All those little waste creators are likely pumping out ammonia, and this is the favorite fuel for algae - and cyano. Letting the scrubber get first crack at the ammonia would be ideal, but in a low flow system, the cyano is right there so it's going to get first crack most of the time...at least, that's what makes sense to me. So back to your scrubber. First, pics would help, so I can see exactly what your setup is (this may affect advice). Also I know that you and I got sideways before on R2R so I want to make sure I have all the information to give you proper advice this time. But generally I would say to make some slow and gradual changes. Usually, if you are at an intensity level that does not result in bare spots on the screen in front of the LEDs, then the first step I would take would be simply extending the photoperiod. Add 2-3 hours, so 14 or 15 hours/day on time. Watch it for the next growth/cleaning cycle and do something to track results, whether that just be photos right before cleaning or weighing the harvested algae (squeezed very well). A small change like 3 hours might not result in something noticable, but if you start to see things like a change in coloration or harvest amount (either way, more or less) then that gives you feedback. I wouldn't jump it straight to 24/7 @ 100%...you might bake your screen (photosaturation). That's why I say extend photoperiod first, if that shows promise, extend a little further, and basically keep going that direction until you see the cyano fade away or you start to see signs of over-lighting. Also correct me if I'm wrong but I seem to recall that you are using 630nm LEDs on your scrubber, or maybe a mix of 630s and 660s?
I had been at 16 hrs. a day prior, but had read your advice that with a LED light 12 hr. was plenty. If I turn up my light intensity, I start getting no growth directly in front of the lights and more around the edges. I think my current level is at saturation. But I can bump up the photo period and see what happens. As for food, I have 6 brood tanks and each has its own feeder, feeding 4 times a day. I feed fresh or frozen each evening as well. I have a vacuum setup and vacuum the brood tanks quite often to remove the left over food, but much remains or gets in the water column. But, with all of that food, my algae scrubber has kept up and my GHA and other nuisance algae are gone. Just a greasy film on the glass. I have read where it is even beneficial, just unsightly.
You got it - when you hit point where you get bald spots on the screen, directly in front of the LEDs, that's photosaturation. I still run one Rev 1 L2 which has 6x 660 on 2" centers with a single royal blue right in the middle, all running at full power, one array on each side. Those back-to-back blues generally kept the screen white right in the middle, and eventually it started to crack and break off, to the point where now I have a 1" hole in the middle of the screen. Are these the lights you are still using or is it a different build: If I looked this up right those are the exotic DRs from LED Group Buy, correct? One possibility is that you can try increasing the flow as you increase the light intensity. The idea being that you are delivering more nutrients per unit time, which should tend to prevent the white spots. I have generally recommended that you don't need much more than 10-12 hours/day when running LEDs. As I have monkeyed around more with my personal setup, either on purpose or by mistake, I figured out that the intensity and duration that you can run without cooking the screen relates very much to the system you are running it on. In my case, my 120 is fed pretty well, moderately stocked (probably on the light side of moderate) and packed with corals, mostly softies (including a 24" x 24" elephant ear leather). It seems that while my nutrients read low, I have not hit a point of over-scrubbing yet, even after months of running 24/7 - which I previously thought would just cook the screen. Compare that to a 4x12 scrubber (L4) on a heavily stocked, moderately fed tank running a skimmer/filter sock/carbon, which grows actually 1/4 the amount of that produced by my 120 in twice the time. If I bump the lights up on that one, I just grow a ton of slime. Still a nice carpet of GHA, but with a slime coating. So it's really hard to pin down a rule that works for everyone, or at least some kind of general guide to how to optimize your scrubber. It's more trial and error, and I don't get a whole lot of people who track and post their growth.
Follow up - still try extending the photoperiod first, before upping the intensity. Also if your cyano is mainly on the glass, this is also just as tough to completely eliminate, as the water from circulation hits the glass and there's your "first crack" algae growth...I've seen some tanks where they claim to never have to clean the glass. Don't know how they pull that off.
The lights you pictured are the ones I am using. You will notice the extra mounting screws. The LEDs were shipped in two batches and after this picture I added two more red and two blue LEDs. Here they are in the scrubber.
