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Algae Grower
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Discussion Starter · #1 ·
Do we have a PAR requirement index for low light plants yet? I’d love to know how much I could dial the light back for my fern and anubias tank.
 

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Algae Grower
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Discussion Starter · #3 ·
Those plants will almost grow in the dark.

When I was low tech, the real trick was very low light and patience. Slow healthy growth is the goal.

20-30 PAR is plenty.
That’s pretty much where I’m at. Growth is more than slow though. I’m also having some issues with bba on the ferns.

I guess my main question is how low can you go with the light levels before it’s not enough?
 

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While I'm not sure on how low you can go (keep turning it down until you see the plants really struggling?) I do know that with low tech tanks, patience is key. It often took years for my low tech tanks of the past to really find a groove and have consistent growth, slow growth but healthy growth.

It's also worth noting mosses, ferns and anubias have lived and grown several months off ambient room light, no direct sunlight into the room at all, for months on end in a half empty tank with no water movement.
 

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I have mosses and java ferns growing with 4 hours of light from this kit, and there are floaters in the tank blocking some of the light. I think it's got just 9 diodes of cool white and is not optimized in anyway for plants, or even viewing fish IMO.

Growth is very slow, especially for the ferns, but there's no algae. I add a pinch of Equilibrium when I change the water if I'm feeling fancy, but otherwise they are just getting fish waste.
 

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Algae Grower
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Discussion Starter · #7 ·
I busted out the par meter. Played with the settings on the lights a little bit.

My light schedule is as follows:

2-3pm, 10 par at the substrate
3-9pm, 20 par at the substrate
9-10pm, 10 par at the substrate

Co2 on at 12:30pm and off at 9. (Not a low tech tank... also dosing pps-pro. Not really sure how much to be dosing considering the light levels.)

My light does way more than I thought it would. Full blast, it’s about 60 par at the substrate at a distance of 22”. It’s 2 satellite freshwater+’s put together as one. (Great coverage plus lots of adjustability..)

Have anyone messed around with light spectrum vs. algae growth?

I probably should remembered I wasn’t necessarily asking a low tech question.
 

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Ambient room light is sufficient. I spent the 60's and 70's with a single 40W incandescent on a 20-gal and rarely had the light turned on. When I did, it was only for a few hours at night and not many nights at that. I was able to "grow" Anacharis, Cabomba and a few others whose names I no longer recall. In fact, even with high-tech, one of the reasons I run CO2 24/7 is because plants awaken almost at the moment of sunrise with the ambient light. I parenthetically called it "grow" because the growth was almost imperceptible. It was more surviving, but the plants did not deteriorate.

Regarding spectrum, I did do some crude experiments with the blue spectrum and did find that GSA increased at lower levels when I added blue. Increased red did not seem to impact algae. This might be expected because the blue wavelengths penetrate much more than the reds. I did not see any unusual development in hair algae or GDA. Again, this was a very crude experiment, although I did repeat the process several times. Other parameters probably influenced the outcome somewhat.
 
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That’s pretty much where I’m at. Growth is more than slow though. I’m also having some issues with bba on the ferns.

I guess my main question is how low can you go with the light levels before it’s not enough?
How close is the nearest window? I have one tank with NO light at all except sunlight about 3 ft away through an east-facing window. Anubias, dwarf sag, crypts and Crinum calamistratum are all growing slowly but steadily.
 

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Algae Grower
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Discussion Starter · #10 ·
How close is the nearest window? I have one tank with NO light at all except sunlight about 3 ft away through an east-facing window. Anubias, dwarf sag, crypts and Crinum calamistratum are all growing slowly but steadily.
It’s about ten feet from a siding glass door. There’s no direct sunlight though.

I think I’m gonna try knocking down the burst and lengthening the low light period to more act like a real photo period. I also have a couple ph controllers laying around. I might hook one of them up for the hell of it. What’s another probe in the tank at this point? Lol
 
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