Internal, bubble-less, oddly-lit scrubby scrub

Hey guys. So my scrubber is definitely atypical.

A bit of background first. My first scrubber was a waterfall version. The screen was large, 12"x8", and powered by a Maxijet 1200, lit on one side by a custom LED array (also an odd combination, more on that later) and the other by a cool white 23w CFL. The LED choice was not 'recommended', but were simply things I had leftover from my various builds and tests. It consisted of four generic 660nm deep red, four generic 450nm royal blue, four generic 405nm violet, and two 5000K Rebel ES whites. Growth could only be called 'immense'.





CFL side



LED side


Very puffy.




So anyway, time goes on, and a few months later, I got scared by some information that I did not understand at a time and reinstated skimming as my sole nutrient export. After that time, despite my best efforts, I was wholly unable to get algae to grow on a screen. I changed the sump from a 40 breeder to a 29g, and got a new Reef Octopus NWB150 skimmer. I attempted several times to grow a scrubber, both in the 40 and 29 sumps. I left the skimmer off for weeks, fed like a madman (which I already was doing), but no growth at all. So I let it go for a while.

A few months back, I purchase a Trigger Systems Ruby 30S sump, which replaced the 29g tank I'd been using up to that point. I now had three chambers, and was determined to get a scrubber going. I didn't want a waterfall scrubber, as I could never get it to be as quiet as I wanted, so I took a sheet of cross-stitch, cut it to fit the center chamber, and have it suspended off of the side using suction cups for super easy removal. I have no aeration, simply a Koralia 4 powerhead in that chamber, both to give more flow to the scrubber and to keep detritus in suspension, which is always a problem for those running no mechanical filtration. The light is simply sitting on the floor of the stand, giving about 8" between the acrylic and the LEDs, like so. They are at a 45° angle to the acrylic both to reduce light hitting the screen while growing in and to keep algae growth on everything else to a minimum until I can figure out a solution.



The light is roughly the same as my original, though there are no 'generic' LEDs to be found - all LEDs are Philips Rebel and Rebel ES, along with LEDgroupbuy 430nm hyper violet. PAR from the light is ~60% more than the original one using the knockoff LEDs (let this be a testament to those trying to decide to buy eBay chips or pay literally the $10-20 more and go with better chips).

The sump was installed May 29th, and the scrubber screen was roughed up and put in that weekend.

Finally in July, I started to see some sludge growing. This was taken July 13th.



After that cleaning, the scrubber stayed pretty clean. I had one spot that was growing true turf algae (you can see it above, not normal hair algae), but the rest just had diatoms. Until now



That was taken yesterday. Growth was thick and heavy, just like I remembered it being! There was also some growth on the unlit side of the screen, but I left it and some patches of algae so that it can regrow faster. Here's hoping that the next batch of algae doesn't take a month and a half to show up!

Anyhoo, I'm pretty stoked now that I can finally grow algae on a screen again, and felt I should share!

If anyone has any questions on the scrubber, my system, or LEDs in general, I'm happy to help out.

 

No, the first and second iterations of the scrubber used the Maxijet, and you can see the results in pictures 3-5.


At some point I am going to change the LED array. I am going to remove the warm white Rebel ES and instead use two Rebel ES lime. I may remove one each of royal blue and violet for lime, as well.

 

I did try and alleviate any nutrient issues by turning off the skimmer, doubling feeding, etc, but I couldn't get anything other than sludge. Everything was the same as before, I had kept the old scrubber screen/PVC contraption. I did forget to mention that later on I put a Mag5 pump on it with the same results (and trying the same thing as before, turning the skimmer off, increasing feeding, etc).

Also, FWIW, I was using the Cobalt MJ1200, not the crappy Marineland clone.


At any rate, have you looked into the Rebel ES lime? I know that algae reflects a lot of green light, but there are accessory pigments that absorb in green, it's also possible that they could help in other ways than just purely growth. Something interesting to test out, anyway. They peak at around 567nm and have a spectral half-width of ~100nm. Really badass LEDs, Philips knocked it out of the park. Now to just get to come up with a phosphor-converted, wide-spectrum blue

 

I guess my 'saving grace' is that pressure was constant since I was not using a cut slot. Water sprayed down from holes drilled in the PVC, and algae never made it up to their due to masking the top couple of inches. The clear plastic also helped distribute the water from there across the algae.

Here's a thread of my review of lime: http://www.nano-reef.com/topic/346477-luxeon-rebel-es-lime-pics-and-par/ A very interesting LED. Extremely high flux and efficiency (almost 200lm/w) and extremely bright to the eye without being overbearing like green LEDs.

 

Yep, those are real-world numbers, too. Roughly 200lm/w at 350mA, 185lm/w at 700mA. Nearing 500lm total at 1A.

 

This is about three weeks of growth, with a twist.






The twist is that almost all of that growth came in about four days before the pics. I had a, uh, miscalculation, on potassium dosing. I originally thought I had dosed 34ppm on Saturday, 20ppm on Monday, and then on Wednesday I was dosing around 108ppm as a test to see what happens with a massive potassium chloride/sulfate dose, if there are any negatives to it. Well, I didn't calculate it correctly. Saturday's dose was 108ppm, Monday's 65ppm, and Wednesday's 325ppm. My original potassium level should have been around 400ppm, so assuming that, my current level is around 900ppm, a little over twice NSW levels.

There was a bit of fallout from the major dose - immediately amphipods died by the hundreds, my fish were having a field day! The next day, however, I noticed that I had lost the majority of my astrea, cerith, nassarius, and stomatella snails, in addition to a brittle star, a serpent star, my two year old hawkwing conch, a chromis, and two springeri damsels. No coral or anemone death occured. If anything, my maxi mini anemones actually look better.

I'm not sure if the scrubber growth was due to the significant increase in potassium or if it was due to the dieoff that occurred. I pulled out the larger snails on Saturday, but nothing else. No water changes or anything, and my protein skimmer didn't have an overly large amount of skimmate collected.

 

Yeah lol. Wasn't too horrible, though.

 

Yes, that's what I was using.

 

That would be awesome. So maybe I increased potassium by 900ppm. Huzzah!

For what it's worth, the miscalculations were because of me and math not being great friends lol

 

Ok, I found your post on RC. I dosed by weight and used that as my calculation (1g giving 129ppm to 1 gallon water), so the numbers above would be correct, just their stock solution stuff is off.

 

Hmm. I measure one tablespoon (which should be three teaspoons) as being exactly 15.1 grams in weight according to a calibrated scale.