DIY Algae Scrubber not growing

[AngryOwl]

Can you post some details about how the tank was started?

Here is the back story on the tank. I started this tank as a 110g system 48x18x30, it wasn't drilled and I was using a canister filter. After 30-45 days I didn't like the setup as it wasn't going to allow me to grow and do what I wanted. So I got my current 120g 48x24x24 tank. In the original tank I had 40lbs live rock and live sand. I moved that rock over to the new tank along with another 60-70lbs of fresh out of the box live rock. Sand was also moved over to the new tank.

I have been running carbon on the system. I fail to see how this could provide an impact though? Additionally, I'm unsure why I would want to intentionally dose the tank with nutrients just for the purpose of feeding a scrubber, only to have the scrubber remove them? I also already feed pretty heavy so I'm not willing to just waste some food for the purpose of feeding the screen.

If you are feeding only 1/2 to 1 cube/day and your screen is 4x9, it's a little big, but not overly big.

The other answer is to not aggressively harvest. I didn't see anything in this thread describing hose often you clean or how vigorously you do so.

Just the man I was hoping would see this post Honestly I should have just bought one of your scrubbers for what I paid total to build this thing.... anyways... for feeding I meant I feed 1 cube + 1/4-1/2 additional, so lets call it 1 1/2 total per day. As far as harvest, I've only done this maybe 3 times? That was to scrub off the diatoms. I don't go too crazy with it. My thought is to not touch it again until I see some real growth.

I think you have done this, correct? I can see the roughness in one picture in this thread - if that's the screen you're using, that's not the problem

Yup, used the teeth of a hole saw. Thanks for noticing

Reef central has a thread - algae scrubber basics in the advanced topics section. It should have all the answers you need

Thanks for the heads up, but I just want to let everyone know I've put hours into researching; not only before my build on how to do it the right way but also on troubling shooting issues. I've been all over the interwebs and the problem is, I see people with somewhat similar issues and they get advice but then there is no true resolution or update. I plan to have both in this thread eventually even if that resolution is I gave up lol.

IMO:

1) it's a bit too big - so you will not want to push it. Meaning, no 24/7 full intensity lighting, not even close to that. Back up to 9 hrs/day @ 50%. You might even drop to 6 hrs/day until you start to get it filled in

2) flow is not a major concern. One pic showed a nice sheet or water coming off the screen - that's plenty. you can get away with lower flow for quite a while, it's only when you are wanting more production that you will need to up the flow (and intensity and hours)

2A) flow, photoperiod, and intensity are all related. Adjust these together, if possible.

3) No need to feed more just for purposes of the scrubber, or resize the screen. You are set up for a nice filtration system once the tank matures

4) Don't overclean, clean enough and correctly (rub & rinse is the name of the game for several months, light brush swiping only, scrub only localized areas, remove all slime/diatoms at least weekly)

hope that helps, I'll be watching the thread for further developments!

Thanks for taking the time to read through the details of this thread and attempt to help figure out whats going on here. At one point I was running the 9hrs per day but I don't think I was at 50%.

I think the gameplan moving forward is this:
Remove the 2 blue LEDS from each side, replace with more reds.
Leave flow where its at for now but I do think I might need to widen my slot slightly because if diatoms get too far up the screen it sprays slightly.
Photoperiod - I'm going to try 22hrs/day at 90-100% for 1 week. No one has told me to do that but I personally want to see what it does. If anyone follows Cj's aquarium they will know he had issues with his scrubber and once he started running in 24/7 its been doing great again. Every system is different I know that so this is my attempt to see if this might work. Whats the harm if I have no nutrients anyways
Also, a heads up, I will be adding more live rock to complete my aquascape. Not 100% happy with how it is right now.

If I have any breakthroughs at all I will update this thread and tell you guys exactly what changes were made. I appreciate all the healthy discussion and assistance!

 

[saltyfilmfolks]

That's true, but there are still many unknowns about what role green light plays.

Splitting hairs dude. We actually know quite a bit. we do know Green plants don't use it. Or it wouldn't reflect it. That's why they are green.


Edit.

 

[Turbo's Aquatics]

Leave flow where its at for now but I do think I might need to widen my slot slightly because if diatoms get too far up the screen it sprays slightly.

If you're getting spray, then you're getting more than slime or diatoms. One pattern I see often (kind of like @TbyZ's growth) is growth around the edges and nothing in the center, or little GHA in the center (his pics are "textbook"). That generally happens when you have available nutrients, but you're blasting the screen with too much light

I'm going to try 22hrs/day at 90-100% for 1 week. No one has told me to do that but I personally want to see what it does.

I would not recommend this unless you have a somewhat mature screen. Meaning, a decent coating of GHA but you're getting slime growing on top of it. And even then, that's usually a phase that will eventually go away. But, I inadvertently flipped the switch on my timer to "on" mode one day about a year ago and thus went to 24/7 lighting, and my growth reflected that - essentially I proved that, at least for me, there is no need for a "dark period". But that doesn't mean everyone should do it.

It is entirely possible that you might trigger growth by going to 90%+ & 22 hrs/day, but it's also possible that it will essentially cook the screen. I guess we're gonna find out

Splitting hairs dude. We actually know quite a bit. we do know Green plants don't use it. Or it wouldn't reflect it. That's why they are green.

Not wanting to derail, my comment there spawned from a conversation I had not too long ago with someone who is in the reef industry and specifically in the lighting area (display tank, not algae/refugium) regarding the ideal spectrum for algae and we had a discussion about specific wavelengths in the green spectrum, and his responses were not something I had heard before (one being along the lines of: after years/decades of research, there are still specific mechanisms that we do not fully understand)

Yes, logic says that green is reflected because it is not heavily utilized. But that doesn't mean that green play no role at all, that's all I was getting to. I was responding to the "only use red because that's all that is needed" comment - basically, red is primary, all I'm saying is that it definitely does not end there

 

[saltyfilmfolks]

If you're getting spray, then you're getting more than slime or diatoms. One pattern I see often (kind of like @TbyZ's growth) is growth around the edges and nothing in the center, or little GHA in the center (his pics are "textbook"). That generally happens when you have available nutrients, but you're blasting the screen with too much light

I would not recommend this unless you have a somewhat mature screen. Meaning, a decent coating of GHA but you're getting slime growing on top of it. And even then, that's usually a phase that will eventually go away. But, I inadvertently flipped the switch on my timer to "on" mode one day about a year ago and thus went to 24/7 lighting, and my growth reflected that - essentially I proved that, at least for me, there is no need for a "dark period". But that doesn't mean everyone should do it.

It is entirely possible that you might trigger growth by going to 90%+ & 22 hrs/day, but it's also possible that it will essentially cook the screen. I guess we're gonna find out

Not wanting to derail, my comment there spawned from a conversation I had not too long ago with someone who is in the reef industry and specifically in the lighting area (display tank, not algae/refugium) regarding the ideal spectrum for algae and we had a discussion about specific wavelengths in the green spectrum, and his responses were not something I had heard before (one being along the lines of: after years/decades of research, there are still specific mechanisms that we do not fully understand)

Yes, logic says that green is reflected because it is not heavily utilized. But that doesn't mean that green play no role at all, that's all I was getting to. I was responding to the "only use red because that's all that is needed" comment - basically, red is primary, all I'm saying is that it definitely does not end there

That's cool. Myths and rumors spread fast.
Folks don't realize aquatic plants and Terestrial plants Share similar adaptations. Nor do most know what color light is where.

It's actually really interesting that everyone is throwing red at macros. Being as it's the first spectrum lost underwater. Jus sayin.

 

[ChrisOFL]

From my understanding of what causes vegetative growth in green plants/algae is that you need a more blue spectrum than red spectrum (this is based on how green plants have adapted to the sun). I know most algae scrubbers seem to use a high red spectrum but I've always had much better success growing green algae with 6700K horticulture bulbs. Dinos are part of the red algae group and prefer that spectrum which is probably why you are growing mostly dinos. Maybe switching the spectrum would get you better growth? Another thing to consider is if your P is so low it may be inhibiting algae growth and dosing it may be required to get the growth started and further facilitate reduction of nitrates.

 

[Larry L]

No algae in the display besides a few diatoms here and there... recently upgraded to a real reef light (photonv2) and getting a little bit more in the tank but nothing crazy.
Nitrate between 10-20
phosphates 0

If there's no algae in the display, and with nitrate/phosphate numbers like this, I wound't be running a scrubber in the first place. If anything I might be dosing a little phosphate.

I'm unsure why I would want to intentionally dose the tank with nutrients just for the purpose of feeding a scrubber, only to have the scrubber remove them?

You wouldn't. It's like the people who you see posting about dosing nitrates and phosphates while at the same time they are carbon dosing and running GFO to remove them...

 

[TbyZ]

One pattern I see often (kind of like @TbyZ's growth) is growth around the edges and nothing in the center, or little GHA in the center (his pics are "textbook"). That generally happens when you have available nutrients, but you're blasting the screen with too much light

Too much light intensity for starting up a screen, not for a mature screen.

As i stated with my pics, i was running the LEDs at 700mA because it wasn't an adjustable set up, & that's the reason for the temporary bare patch.

But don't be mistaken, once the screen was fully covered this intensity was perfect.

If i had had an adjustable setup i would have started the LEDs at 500mA & the temporary bare patch wouldn't have occured; not that it was a negative at the end of the day anyway.

 

[TbyZ]

From my understanding of what causes vegetative growth in green plants/algae is that you need a more blue spectrum than red spectrum (this is based on how green plants have adapted to the sun). I know most algae scrubbers seem to use a high red spectrum but I've always had much better success growing green algae with 6700K horticulture bulbs. Dinos are part of the red algae group and prefer that spectrum which is probably why you are growing mostly dinos. Maybe switching the spectrum would get you better growth? Another thing to consider is if your P is so low it may be inhibiting algae growth and dosing it may be required to get the growth started and further facilitate reduction of nitrates.

Most people run a heap of blue for their tank lights. Try running red instead and see what happens.
Algae everywhere i guarantee

 

[ChrisOFL]

Most people run a heap of blue for their tank lights. Try running red instead and see what happens.
Algae everywhere i guarantee

Maybe but then again the most common algae outbreak under blue lighting seems to be GHA/Bryopsis. The only point I was making is that a warm white spectrum for vegetative growth might get him better results than a deep red spectrum. Green algae prefers different lighting than red algae.

 

[TbyZ]

Maybe but then again the most common algae outbreak under blue lighting seems to be GHA/Bryopsis. The only point I was making is that a warm white spectrum for vegetative growth might get him better results than a deep red spectrum. Green algae prefers different lighting than red algae.

The red 660s, as far as using LEDs is concerned, has been proven to be the most effective. This is why manufacturers like Bud & SantaM use predominately red.

 

[stevieduk]

Back in late August I built a algae scrubber. To this day all it has grown is diatoms...

Info about the scrubber:
Waterfall style, screen is about 9" x 4", uses an individual pump to supply flow 295gph pump and most importantly the lights... rapidled solderless leds, 4 reds and 2 blues on each side. (6 leds per side). Controlled by a dimmable driver. Leds were basically copied from kingofdiy supercharged algae scrubber video.

Started the scrubber running 18hrs per day at maybe 15-20% power. Only diatoms grew. Did this for 3 weeks.
Read some stuff online then switched to 9hrs per day at maybe 25-30% power. Did this for 2 weeks. Still nothing...
Kept the lights running 9hrs per day but increased lights to nearly 100%, maybe 90%. Left it like that until 2 weeks ago when I changed it back up to 12 or 14 hours, can't remember... the point is still no growth.

Any thoughts on what's going on here? There has been no hint of green growth, only diatoms. Side note about the screen before someone says it... Yea it's rough, very rough, I used sandpaper and then a drill bit used to drill holes (like for bulkheads or doorknobs).

Tank info:
Setup 4 months ago
120g with emerald 39 trigger sump
8 fish 2 shrimp
Feed twice per day about 1 cube or more per day
Used tap water until 2 weeks ago when I got an rodi system
No algae in the display besides a few diatoms here and there... recently upgraded to a real reef light (photonv2) and getting a little bit more in the tank but nothing crazy.
Nitrate between 10-20
phosphates 0

No idea what's going on here. Thinking of taking it down and trying a refugium. Let me know your thoughts!

think your lights are to fancy, just use any old cheap white lights for good algae growth

 

[TbyZ]

think your lights are to fancy, just use any old cheap white lights for good algae growth

Show us your algae growth.

 

[ChrisOFL]

The red 660s, as far as using LEDs is concerned, has been proven to be the most effective. This is why manufacturers like Bud & SantaM use predominately red.

I'm pretty sure the reason red is used is because it grows a larger variety of algae than if you were to use only a blue spectrum. Chlorphyll A and B (found in all green plants/algae) have peaks in both the blue and red sprectrums which is a product of evolution. Blue light tells green plants its time to veg out and then when the light shifts to the red spectrum the plants know its time to flower. Marine algae is a little simpler but the same rules apply. However, green plants will grow under red light but "better" is subjective.

 

[Turbo's Aquatics]

Chlorphyll A and B (found in all green plants/algae) have peaks in both the blue and red sprectrums which is a product of evolution.

However, green plants will grow under red light but "better" is subjective.

I agree with this, a lot of fixtures use the cheapest LEDs & substrate they can, with no binning/selection so results can be all over the board. Also people tend to ignore intensity, which has a large impact at various stages. So collecting anecdotal data is very unreliable.

Also, most off-the-shelf "grow" lights are made for plants - either "grow" or "flower" stage lights. The former are typically a red mixture + royal blue. These usually work OK for algae scrubbers, but the reason they use RB is they are the most common, cheap, and generally reliable. They don't use Violet because they are much more expensive and most are subject to delamination over time - but Violet (HV=Hyper Violet) works better than RB, and the combination of DR (Deep Red 660nm) + HV works best when the violet is muted (lower current than red). Also RBs running at the same current as DRs will output many times more radiometric flux, which is why you get hotspots when RBs are in play like that. HVs are more on the same level (intensity at a given current) as DRs but they are still supplementary, so I still wire them up in parallel or dim them separately - you don't need much.

 

[Turbo's Aquatics]

Talk about over doing it, I'm trying not to scream, it's not rocket science, come on..

I don't think this is over-doing it. It's knowledge that I've gathered from years of working with and observing others, as well as experimenting with my personal units.

While I appreciate wanting to keep it simple, and not turning it into rocket science, I have a lot of knowledge and experience to share that is a result of building, selling and maintaining scrubbers as well as year of helping others troubleshoot them. There are certain things that work better and certain reasons why a scrubber has issues. I go into long explanations about why because it interests me and I like to share, and there are probably other nerdy people out there that like reading that.

If that bothers you, scroll on past. I wasn't intending on derailing the thread but that happens on occasion.

For the nerds who want to continue to nerd out:

It comes down to this:

There is a ratio of about 6:1 Red:Blue that seems to work best. Cornell and NASA did a few studies that showed this. But it's not as simple as that being just the number of LEDs, it's more of a radiant flux/delivered power level. So you can't just put 6 reds and 1 blue together and call that "the ratio". I know from experience. Cutting the blue intensity in half and going with 2 blues reduces the overall blue component, but it's still a bit much usually. Going to violets made a noticable difference in speed of developing a new screen as well as increasing actual growth (at the same intensity)

630 Red is too intense, that's more on the level of output of a RB compared to an HV. I spoke with hydrponic fixture manufacturers that prefer to use 630 because it has 3x the flux output of 660, but when you're shooting for even coverage and avoiding hotspots with lights in close proximity to the growth substrate, 630 just doesn't work well and usually causes photosaturation issues

 

[AngryOwl]

Talk about over doing it, I'm trying not to scream, it's not rocket science, come on..

If you have knowledge, experience or constructive criticism please pass it on so everyone reading can get better and learn.

 

[AngryOwl]

From my personal experience, I use the mix , I've found this out with my own testing, I've ran the solid mix and 6500 with the mix diodes, there is a benefit in mixing whites in, the solid mix, witch is the 660 and 450nm is 4 to 1, it's not rocket science, there's such a small difference in growth , it's not worth it, imo the mix with the 6500 and the mix , is the bees knees, no limit on the size you can make

What kind of LEDs are those? Interesting including the 6500, haven't seen that done before but would be consistent with people using simple regular light bulbs.

 

[mcarroll]

I have been running carbon on the system. I fail to see how this could provide an impact though? Additionally, I'm unsure why I would want to intentionally dose the tank with nutrients just for the purpose of feeding a scrubber, only to have the scrubber remove them? I also already feed pretty heavy so I'm not willing to just waste some food for the purpose of feeding the screen.

I'm not sure that's the point anyone was making, but let's look at the concept of "feeding the screen".

If the screen has algae on it, then by definition you're feeding it. Some percent of what you feed is going to the screen. It's not going to corals in the display tank – that's for sure. Ergo it is waste.

This is neither pro or con to running a scrubber, but we can afford to be honest about where the nutrients come from and where they are going.

That generally happens when you have available nutrients, but you're blasting the screen with too much light

True!!

Photosynthesis is a tough row to hoe, wether you're an algae or a coral*! A mature bloom will have self-shading capabilities as well as much more developed detoxification regimes. Mature cyano mats have an incredible enzymatic ability to process H2O2, for example. I'm sure similar is true of other forms, more or less.

* Is the coral-algae symbiosis really ‘mutually beneficial’ for the partners?

 

[AngryOwl]

Update:

LEDs came in yesterday and got those installed, nothing but red in there now. Also I found a broken wire on the back side LEDs... so not sure if I broke it replacing the LEDs or it somehow broke in there? Pretty sure I broke it... but all fixed now and both sides nice and red. I'll post another update in a week.

 

[AngryOwl]

Hmm, either do I see slightly green growth starting to form? This pic was 2 days ago, gotta check again tonight.