The Great Algae-Light Source Experiment

[Floyd R Turbo]

PURPOSE: Design and implement an experiment utilizing the Scientific Method to determine growth rates of algae under various light sources in an Algae Scrubber system on a marine aquarium.

I started this thread based on the discussion in this thread

viewtopic.php?f=2&t=1253

And the apparent need to actually design and perform this experiment in order to get an answer to this question. This will likely not be a "once and for all" type of result, but hopefully it will provide enough data to satisfy the majority of our curiosities, and maybe it will point us in the direction of a more refined experiment.

This will be a collaborative effort. All suggestions will be considered.

I will volunteer manufacturing of all acrylic boxes required for said experiment.

At this point, I open this up for all suggestions about the criteria, specifically, the source of light and configuration of the experiment.

It has been suggested on the other thread to start with various mixtures of LEDs, and construct multiple Algae Scrubbers functioning on a single system, such that all devices are driven by the same set of "input" water parameters. So let's start with that...

[Floyd R Turbo]

Ok, back from giving the kid a bath. It was suggested that a system would be designed such that there were multiple small scrubbers all fed from the same system, such as a large tank with a 55g sump and a series of scrubbers all fed from the same overflow and split into multiple branches, with a common return pump. Each individual scrubber would have equal flow and different light configurations. So that is one possible idea.

Another possible idea would be to set up a series of smaller systems and different scrubbers.

However this is done, in order to be a controlled, I would think the most reasonable way to do without introducing too many variables is to eliminate the fish, rock, corals, sand, etc. Just have bare empty tanks and dose given amounts of nutrients equally to each system. This would initially be a low-cost and easily reproducible experiment, and a control group could also be easily used. Although it would hardly be real-world, I see it as the only way of growing algae under perfectly controlled conditions.

Otherwise, using the large single tank idea, you would have to make sure the tank was full of rock that was fully cured, and the system would have to have long-term stability, perhaps 6 months to a year of operation before the 'experiment' could start.

Although you could do a large bare tank and multiple small filters. However I wonder if there would be introduction of competition of species if one scrubber grew more efficient algae and out-competed another scrubber. Results would be skewed.

[sublime]

Awesome -- I will be very interested to read the progress of this thread and contribute when I get back next week. I wish I was not headed out right now... oh wait, yeah I do... we will have a lot fun and it will be a much needed vacation.

Thanks for creating the new thread Floyd.

Brandon

[sublime]

Ok, back from giving the kid a bath. It was suggested that a system would be designed such that there were multiple small scrubbers all fed from the same system, such as a large tank with a 55g sump and a series of scrubbers all fed from the same overflow and split into multiple branches, with a common return pump. Each individual scrubber would have equal flow and different light configurations. So that is one possible idea.

Another possible idea would be to set up a series of smaller systems and different scrubbers.

However this is done, in order to be a controlled, I would think the most reasonable way to do without introducing too many variables is to eliminate the fish, rock, corals, sand, etc. Just have bare empty tanks and dose given amounts of nutrients equally to each system. This would initially be a low-cost and easily reproducible experiment, and a control group could also be easily used. Although it would hardly be real-world, I see it as the only way of growing algae under perfectly controlled conditions.

Otherwise, using the large single tank idea, you would have to make sure the tank was full of rock that was fully cured, and the system would have to have long-term stability, perhaps 6 months to a year of operation before the 'experiment' could start.

Although you could do a large bare tank and multiple small filters. However I wonder if there would be introduction of competition of species if one scrubber grew more efficient algae and out-competed another scrubber. Results would be skewed.

I agree... that is why I was thinking of running the lights all on the same screen vertically. Split the same screen up into 3 "sections". Just run optics on the LED's and small black ABS pieces to keep most of the light separated. They way I see it, one would do better, and you might even see the small areas where they mix do the best. You then take the info learned from this "stage 1" and move to stage 2 along the lines of what you are talking about. The idea of the LED's on the same screen is to reduce competition and get a base line to know what to dive deeper into. Taking it to the next level, I think that more diversity in tanks is more important that strictly controlled nutrients doses. (remember I am big into math and stats) I think we should take a statistical approach on this and just create "bio-load weights" that we determine as a group. I was already wanting create a scale for another experiment I am doing for tank bio-load and design. There would need to be a few constants though such as screen size, flow rates and overall light intensity to be effective. However, different nutrient levels and different tank sizes should not matter at a stage 2. Moving to a "stage 3" we could look a very controlled experiment where there are clean closed systems that have various levels of nutrients added over time. I think though, with the first 2 stages we could learn enough to get close to the answer we are searching for to some degree of satisfaction. When I get back, I would be glad to share my VERY simple acrylic design for what I think should be the base line design for this experiment. Then, we can tweak it a bit if someone else can come up with a better design and or idea.

This will be my last post until next week. Keep it up folks!

Brandon

[Floyd R Turbo]

I just wonder if running everything on a common screen as you suggest with sections of different light might actually produce slightly different algae, which would then tend to induce competition, not reduce it. That is why I was thinking of multiple independent systems. So I'm not quite following you I guess. One of our local schools has a marina biology department with over 10,000 gallons of system water (I think it's more like 16,000) and I'm wondering if they would have the capability or the interest in analyzing the algae from each system to determine if there is actually different strains being produced. So the independent systems idea might have other benefits in that regard.

Also MACNA is in town in September. I think that it would be killer if I could coax a few of the 'experts' that will be there into stopping by and looking at an experiment in progress. Talk about an opportunity to spread the word...

[Ace25]

Been brainstorming some more myself.. I think I have a sweet design for an experiment.. in my head anyway. It is very similar to Santa Monica's scrubber. Lets see if I can describe it. Just a simple ABS box, about 18"wide x 4" deep (with bigger bottom plate for stability) x 12" tall. So you have a black box so far on a large base. On my setup I am thinking the base can be as wide at the top rim on my sump so I can just set the ATS right on top on the sump. Next cut holes on the side panels at the top for the pipe that will hold the screens. Make ABS dividers/baffles and cut the same holes at the top for the pipe, put in 4 dividers evenly spaced to give you a little over 3" per section. Now you have a black box with 5 distinct sections that are 3-1/4"x12". Next, drill holes on the outside walls, 2 holes vertical on each chamber, large enough for LEDs to fit into. Glue small pieces of acrylic on inside to water seal the holes, or better yet, piece fit perfect for the inside part of the chamber. Mount 2 LEDs per side on channel aluminum, per section, so 4 LEDs per section for a total of 20 LEDs which means only 2 drivers, one driver for all LEDs on each side. Drill a drain hole at the bottom, install bulkhead, install pump, cut 3" slots on pipe with table saw, prepare screen and cut into 3"x10" strips, and put it together. Anyone understand that or does it only make sense in my head. LOL

What I picture in my head is something similar to coffee bean dispensers you see at the grocery store, tall narrow sections side by side.

[Ace25]

Another idea I just had, make the box deeper, 8-10", and for the holes for the LEDs drill them so optics will fit perfectly through the hole, then a little silicone around the optic to water seal it and all done. As long as you make sure all the LEDs are spaced correctly on the C channel you should be able to easily remove the LEDs and make changes as the experiment moves forward (thinking velcro to secure them to the box, bottom will be resting on the base so no weight pulling on it). It is only 2 LEDs on a good size piece of metal and run at 700mA, so no fans should be required.

[Floyd R Turbo]

That sounds interesting, I hadn't really considered the idea of making the 'black box' and then drilling holes for the LEDs. I would likely build mine to mimic Rygh's builds, which involve using a diffuser to blend and even out the light. Just poking LEDs through holes and having them 1-2" from the screen is not going to work, IMO. Putting lenses on them will make it worse. I believe that we need to have as even coverage as possible.

In fact, on that note, I think that one of the 'control group' systems, besides a non-scrubber system, should be T5HO and another CFL. This will give us opportunity to also perform a benchmark comparison test between the different sources of light.

All this being said, I am not against someone else running an experiment that they deem to be valid. Right now I'm thinking that I have a basement storage room that needs to be cleaned out anyways, and I could easily build a rack of tanks and run a couple of circuits down there...the mad scientist in me is waking up...

[Rumpy Pumpy]

Excellent!

I'll look forward to seeing this unfold

[Floyd R Turbo]

What would one use as an additive to create a 'soup' of nutrients to feed the screens in a bare-tank system?

At a minimum, I would be needing a source of N and P. Dry ferts used for planted FW tanks would seem to be appropriate, but if I'm trying to duplicate what is created in nature, is there something more complex?

Still thinking of other parameters for / thoughts about the multiple independent bare tank experiment.

1) If I want a control group using T5HO, then I would be restricting all screens to 20" wide and 3" tall, minimum, for consistency. If I'm running on 10 or 20 gallon tanks, this is way overkill filtration and flow. Maybe should ditch the T5HO control group idea.

2) I will need to account for cycling of the system, or pre-cycle the tanks. Perhaps using a small amount of live sand or commonly cured base rock rubble. Again, throwing a potential variable in there, but I do have a 25g container full of small pieces of dry rock that I could cook up in a common container.

3) Each system will need to be on the same display tank lighting cycle and scrubber lighting cycle. Simple enough to do with some SunBlaze T5HO strips with tanks ganged together over the display tank section.

4) A dosing pump system would be used to provide consistent nutrient loading of each system. Probably one pump with some kind of manifold to split the dosing across all systems, so that differences in individual doser units is eliminated.

5) The system would be saltwater based (figured that was worth mentioning)

6) Each system would be identical in all ways except the source of light: same materials, piping, overflow, contents, same brand and model of feed/return pump. Each pump would be tested for flow rate verification.

Scrubbers will likely be located above the tank for ease of design (no sumps). But undecided about making them in enclosed boxes. But I just had a bright idea. Since I'm setting up my acrylics fabrication shop, I might as well make my own system. I could make a one or two long tanks and put in dividers, add bulkheads, then make a second set of tanks below that would house the ATS units. These could have one common display tank light system and everything else would be isolated, as long as the welds were all bubble and leak free. This way I could make the ATS units rigged for enclosed 3D growth to maximize results.

Hmmm...