Hi, I've got a JBJ 28, the AIO flow pattern/setup kind of confines me to a simple submerged screen right off the overflow teeth. I have a led shining right in the back at the 4x4 screen. Anyway, I've got 4 Steves Luxeon deep red (in a square), and one of the new true violet in the center. They are running on at 700 H LDD, dimming with Arduino analogWrite thingy (fast flashing not current dimming). Anyway, I've let my screen sit in the water 2 weeks without light, then 1 weeks at 20%, 1 weeks with 30% and now I'm on the 4th week at 40%. No significant growth on the screen yet, but the glass between the light and screen did get some build-up. I do have massive hair algae growing in the display. I do about 1+ % water change per day via arduino and float switches. I also use the poly bio marine polyfilter organic absorbant sponge thing, easier than GAC and seems gentler... No skimmer, one fish, light feeding, started with dry rock from bulk reef supply. Should I jump the intensity up or just wait it out? Thanks!
I would start out at 50% minimum. 100% will work fine also and then just vary the photoperiod. But then why would you want to do that, since you have the Arduino to make fancy things happen, right? Lets check a few things first though: Screen is submerged Doesn't sounds like an upflow How many hours/day are the LEDs on? Pic?
Yes, it's totally submerged. Water is flowing down, it's coming down through the DT overflow. No air pump or bubbles, I already get enough salt creep right at that point from the overflow... I've been running from 7PM to 8AM. I'm looking for a reverse photo-period, but just sort of picked on and off times from thin air. DT right after removing about a 1/2 pint of long hair algae from rock and gravel... Back of tank with LED mounted (it's turned off at the moment). The LED is held on with Velcro, here is how the screen lines up with the LED. Another shot of the screen, the algae hanging on the top is from the DT. Pieces tear loose when I clean the DT and go through overflow and get hung up on the roughed up screen. This is the top, back of the tank, water coming out the overflow. That is my access point to pull the screen up and out, it's held by two pieces of black acrylic with a cut running up the middle to slide over the overflow chamber side walls. Here is my LED layout: All LEDs from Steve's, middle is one of the 3watt true violet version 2.0 (419 nm). Thanks, Kenneth.
I think it might be a flow problem. Can you raise the screen up so that it is partially out of the water, with the top edge right at the bottom of the notches of the overflow, then angle it slightly to force the water to run down the screen? Then the underwater portion will get much better flow, and the upper part that is out of the water now will become a true waterfall. The submerged screen "not working" concept I believe was because it didn't seem to work as fast as the true waterfall. So it was set aside and poo-pooed. Then SM came out with the upflow and bubbles etc and this was purported to be the solution (bubbles for flow). I have pretty much disproven this need at least partially myself, as my L2 UAS tester which has a very clogged bubbler device but a good amount of flow through the enclosed box does a great job of growing algae everywhere inside it, even when the screen is not anchored properly. But submerged screens, in whatever form they take, need much more time to cure and become useful. So if you take a waterfall and submerge the bottom of it, the waterfall becomes powerful enough to disallow growth on the less effective submerged area. But if you take the waterfall out of the equation, the submerged section will grow, over time. But that is the key - it takes time, and a lot more of it, especially in a saltwater system, and especially in one with an in-tank scrubber (algae on rocks). This is why I highly recommend raising the screen up out of the water and letting the overflow flow over it. I would be very interested to see if and how quickly algae starts growing on both areas of the screen.
That makes sense on the screen mounting, I wish I would have thought of that originally... I'm going to have to figure out how to rig that up, as the clips I made won't take the screen that high. Do you think if I add a small power-head into the overflow chamber, under the screen and aimed back up at the screens' bottom lip, I could help the flow problem? In the meantime I'm going to increase the LED intensity to 50%, and I guess leave the 11 hour photo-period.
Looks like you could just drill 2 new holes in each side of the acrylic and zip tie your screen up higher - from the pics that appears to be how you originally mounted it to the acrylic so it should be adjustable to whatever height you need with a couple quick shots of the drill and 4 new ties.
That is a good idea, I just didn't make the clips tight enough to hold on an angle. The tops stick up a little too far too, so I'll need trim those up. I also need to run the velcro strips up higher on the tank for the light mount. I actually decided to just let the ATS go a while longer as is because I needed to switch over and focus my time on my DIY DT LED setup. I have had the original DT CF bulb in this JBJ for over a year now at 6hrs per day, and I think that's just helping my DT algae problem. I'm finishing up building a more blue dominate LED setup to replace it, and I'm hoping the DT algae will struggle more and push growth back to the ATS red bulbs on the screen. I did notice copepods crawling the screen last weekend when I checked it out and scrubbed the algae off the back glass, so that is promising. I also increased the photo-period to 14 hours and the intensity to 60%.
Sorry for the late update. I did finally move the screen up out of the water and on an angle, the exposed screen and that near the surface grew nicely. But it did make a big salt creep mess on the back of the hood. I submerged it again then but put a Koralia 3 under it, no real algae growth. Then I moved it all the way down in that chamber, and removed the Koralia. The screen started to get some coralline aglae, then it got a nice layer of cyano. I made other changes to my system and drastically reduced fish and feeding. Algae is under control for now, but I keep the light on down there on a reverse daylight cycle. I've removed the screen, but I do have it shining on an old piece of ReefresH2O I had lying around. I need to check it one of these days to see if it's growing coralline again, flashlight checks down the back hole though seem to indicate it's clean. I do pull off the light every two weeks and run a magfloat back down that glass to keep any light blocking build up off. I'm hoping now just to keep the pH more stable with a reverse daylight setup, plus the eerie red/purple light make the living room more fun at night...
