Sorry if I missed this on the forum somewhere but surely there must be a pretty standard way of determining how much LED lighting you need for a tank? In the old days (yes I am OLD) we used watts per gallon. That won't work here unless I guess something can figure out what the watt equivalent is for LED lighting. I have a 180 gal planted that I am slowly converting from VHO to LED but I have to say that at least inch for inch the LEDs (Finnex Planted Plus) don't come close to matching VHO. So before I go too much further I figure I would try to calculate how many rows of LED lighting I will be needing to properly grow med and low light plants in my 180 gal
Calculating the right amount of LED Lighting?
- Thread starter Evad
- Start date
MattArmstrong
Member
Watts/Gallon has become PAR. PAR stands for Photosynthetically Active Radiation. It is the a measure of the light photons that are within the light frequencies used by plants (generally the blues through the reds -- quite similar to the light we can see). I think PAR has become popular because PAR meters became (semi) affordable and watts/gallon became useless with the many different kinds of lights available now.
I have looked for the "one true" web site that explained all of this clearly, but haven't found it. Maybe someone else has and can post a link. For now, I'll just explain what I've discovered over the past few months.
If you want to geek out, you can become a member of http://www.gsas.org/, check out the club's PAR meter, measure the PAR your current lights get you, and attempt to match what you currently have with LEDs that claim certain PAR output. You would also then know if you're looking to implement what today is called low, medium, or high light. The PAR ranges for each is up for debate, but generally people agree that "low PAR" implies no need for CO2 or even a lot of plants, "medium PAR" suggests that you should have a good number of plants and CO2 may be useful or you'll at least need to keep the lights on a timer with short on times to avoid algae, and high light definitely needs lots of plants and CO2 to avoid algae issues.
Trivia: a measure that attempts to capture how useful a light is for plants is called PUR (Photosynthetically Usable Radiation). Nobody uses PUR to judge LEDs because the science isn't there. Every plant absorbs light differently, and there is even conjecture that plants adapt to the spectrum they are receiving.
If you want to see a PAR meter in action (in fact, I think it is the GSAS par meter), you can see Cory using it in this video:
[youtube]-I-fUrI5mwo[/youtube]
and this:
[youtube]vD7QaRzf1Qw[/youtube]
Recently our member Vickmak did some comparisons with the same PAR meter and reported results in this thread: http://www.wafishbox.com/forum/viewtopic.php?f=22&t=11395.
My guess is your 180 is two feet deep. "Word on the net" is that the Finnex Planted+ gets you medium to medium high light, and is suitable for tanks 18" deep and shallower. At two feet you're into more serioius territory. E.g. Finnex Ray2 or even http://www.buildmyled.com/'s XB series. You can go even higher end (but buildmyled is as expensive as I've ever researched).
Note: the buildmyled people suggest that if your tank is 18" or more front-to-back, you're better off with two strips.
The buildmyled site has an estimator tool. Choose a light (e.g. the "dutch planted") and it'll ask you your tank size and desired light intensity. It'll then suggest how many lights to get. They also suggest you get a dimmer, as generally when you get just 2 or 3 light strips you'll want finer control than turning your lights on and off in thirds. Looks like you're at almost $1,000 to go through them!
There are budget friendly DIY approaches, especially if you have a canopy to mount stuff in. I'll let others comment on those ... I've ignored them because I have an open top tank, no canopy.
My personal story is that I've got a "Fluval Aqualife" over my 3 foot open top tank. It was too bright, so I bought a "Current USA Ramp Timer Pro" to dim it. I don't recommend this approach if $$ is a concern -- I got poor value for my money. I think I could put one or two Finnex Stingray on my tank and be quite satisfied.
I have looked for the "one true" web site that explained all of this clearly, but haven't found it. Maybe someone else has and can post a link. For now, I'll just explain what I've discovered over the past few months.
If you want to geek out, you can become a member of http://www.gsas.org/, check out the club's PAR meter, measure the PAR your current lights get you, and attempt to match what you currently have with LEDs that claim certain PAR output. You would also then know if you're looking to implement what today is called low, medium, or high light. The PAR ranges for each is up for debate, but generally people agree that "low PAR" implies no need for CO2 or even a lot of plants, "medium PAR" suggests that you should have a good number of plants and CO2 may be useful or you'll at least need to keep the lights on a timer with short on times to avoid algae, and high light definitely needs lots of plants and CO2 to avoid algae issues.
Trivia: a measure that attempts to capture how useful a light is for plants is called PUR (Photosynthetically Usable Radiation). Nobody uses PUR to judge LEDs because the science isn't there. Every plant absorbs light differently, and there is even conjecture that plants adapt to the spectrum they are receiving.
If you want to see a PAR meter in action (in fact, I think it is the GSAS par meter), you can see Cory using it in this video:
[youtube]-I-fUrI5mwo[/youtube]
and this:
[youtube]vD7QaRzf1Qw[/youtube]
Recently our member Vickmak did some comparisons with the same PAR meter and reported results in this thread: http://www.wafishbox.com/forum/viewtopic.php?f=22&t=11395.
My guess is your 180 is two feet deep. "Word on the net" is that the Finnex Planted+ gets you medium to medium high light, and is suitable for tanks 18" deep and shallower. At two feet you're into more serioius territory. E.g. Finnex Ray2 or even http://www.buildmyled.com/'s XB series. You can go even higher end (but buildmyled is as expensive as I've ever researched).
Note: the buildmyled people suggest that if your tank is 18" or more front-to-back, you're better off with two strips.
The buildmyled site has an estimator tool. Choose a light (e.g. the "dutch planted") and it'll ask you your tank size and desired light intensity. It'll then suggest how many lights to get. They also suggest you get a dimmer, as generally when you get just 2 or 3 light strips you'll want finer control than turning your lights on and off in thirds. Looks like you're at almost $1,000 to go through them!
There are budget friendly DIY approaches, especially if you have a canopy to mount stuff in. I'll let others comment on those ... I've ignored them because I have an open top tank, no canopy.
My personal story is that I've got a "Fluval Aqualife" over my 3 foot open top tank. It was too bright, so I bought a "Current USA Ramp Timer Pro" to dim it. I don't recommend this approach if $$ is a concern -- I got poor value for my money. I think I could put one or two Finnex Stingray on my tank and be quite satisfied.
A
Anonymous
Guest
1 Finnex Ray2 is close to the equivalent to a duel bulb T5HO. To get moderate light to the substrate of a 2 foot deep tank you will need to go 3 Finnex LED strips across. I have a mixture of Ray2 and Planted + fixtures on my 2 foot deep tank. If you wish to have a highlight tank you'll need to go 4-5 rows of Finnex lights.
A
Anonymous
Guest
MattArmstrong
Member
Wow, that Finnex set up is ... a lot of Finnex!
Super helpful everyone! I suspect that even three strips wont quite do it, but going to start with another strip across and see where that gets me. I don't really want to get back into CO2, but would prefer to use Excel and a shorter photo period. I am really struggling with my Green Hair Algae problem and wonder if the plants are not getting enough light to consume all the nutrients in the 7 hour photoperiod I am giving them.
Thanks!
Thanks!
A
Anonymous
Guest
Evad said:
I can totally relate to this. It's not like one day I went out and purchased 10 LED fixtures. I was running T5HO and very cautious with LED fixtures. Researching, consulting, more research. The fact is at the time I couldn't grasp the lingo with this new to the hobby technology. Years was spent learning fluorescents, all the different types , spectrums, ect.
At the time even if there was a mathematical way to compare the technologies it was too complex for me to care, lol!
I purchased my fixtures one at a time. Over the caurse of about 18 months ended up satisfied with what I current have installed. One nice thing was the investment was over a period of time. That and the fact the LFS gave credit for the plants i was growing, + 10% off woth a GSAS discount took the edge off a bit
Don't forget this tank is also 2 feet deep. Being 7 foot long amd only 16" from front to back is the main reason you see the fixtures so close together. I do not know the PAR values but can tell you i can grow just about anything. Ground covers however are a challenge. S. Repens, A.R. mini, Pogostemon helferi, these where a no go. But small cryptocoryne species, small chain swards, ect do very well. I am current trying dwarf hair grass. I am in my second week with this plant and I am seeing runners. So, fingers crossed.
A
Anonymous
Guest
Thread algae could me one or a combination of things. Some reading suggests an over abundance of iron. However, like most algaes they can be out grown with a fast growing plant/system with proper lighting and nutrients. The introduction (if you havent already got them) of SAE. Siamese algae eaters help maintain this type of algae.Evad said:
Here is a recent photo of my large planted tank. Most plants have been introduced within the last 3 months. The "small" Chain sword in the front is a good 2-3 months old now, the background plant is about 4-5 weeks old. It was one large plant I split into 5 stems throughout the 7 foot tank. The left side front is bare, just planted hair grass there. The left side I started small cryptocoryne so it's still bare. If the hair grass does well I plan on replacing the small chain sword. The big wood in the middle just got new ferns on top and anubias planted on it just a couple weeks ago. I think I'm going for a full out jungle look here, lol.
Seattle_Aquarist
Well-Known Member
Evad said:
Hi Evad,
I seldom have issues with green hair algae (not Cladophora) except during the start-up a new tank when the nitrogen cycle is just becoming established and ammonia is present. If this is an established tank (i.e. over 45 days) I would suggest testing your water for ammonia, nitrites, and nitrates. Adding a Siamese Algae Eater in conjuction with dosing with Excel / glutaraldehyde usually gets it under control.
MattArmstrong
Member
Increasing light to combat algae is an unusual tactic!Evad said:
From Tom Barr: Plants out-compete algae when light is the limiting factor. Algae out-competes plants when anything else is the limiting factor (not enough of a fertilizer or CO2 to match the given light). Give plants the ferts and CO2 they need for the light they get and the tank will do fine. This was the subject of his 2010 talk at GSAS: "The Light-Limited Planted Aquarium". It is OK to reduce light and provide an excess of CO2 or fertilizers: plants will out-compete algae in that scenario.
This matches the conventional wisdom of "reduce light when algae strikes." Put another way: plants do better in low light than algae does.
His other message is that plants take longer than algae to adapt to new parameters. In lower light, lower fert, low CO2, tanks, attention must be paid to keeping things stable. He goes as far as saying very few water changes in low tech tanks. Algae "strikes" when parameters change (sudden influx of CO2 from a water change, new ferts, different light levels, new tank, etc.). Given stable parameters plants can reconfigure themselves, to a certain extent, such that they out compete algae. In high tech planted tanks this is less an issue; the plants are dosed CO2 so additional CO2 from a water change is not an issue.
In my tanks, I'm finding this works. I reduce light whenever I see algae and focus on maintaining a stable regimen (e.g. consistent but not excessive fertilization). I see cleaner plants, less algae, better growth. My 4 gallon tank has no fish and so I don't change the water much at all, and it is doing the best.
MattArmstrong said:Increasing light to combat algae is an unusual tactic!Evad said:
From Tom Barr: Plants out-compete algae when light is the limiting factor. Algae out-competes plants when anything else is the limiting factor (not enough of a fertilizer or CO2 to match the given light). Give plants the ferts and CO2 they need for the light they get and the tank will do fine. This was the subject of his 2010 talk at GSAS: "The Light-Limited Planted Aquarium". It is OK to reduce light and provide an excess of CO2 or fertilizers: plants will out-compete algae in that scenario.
This matches the conventional wisdom of "reduce light when algae strikes." Put another way: plants do better in low light than algae does.
His other message is that plants take longer than algae to adapt to new parameters. In lower light, lower fert, low CO2, tanks, attention must be paid to keeping things stable. He goes as far as saying very few water changes in low tech tanks. Algae "strikes" when parameters change (sudden influx of CO2 from a water change, new ferts, different light levels, new tank, etc.). Given stable parameters plants can reconfigure themselves, to a certain extent, such that they out compete algae. In high tech planted tanks this is less an issue; the plants are dosed CO2 so additional CO2 from a water change is not an issue.
In my tanks, I'm finding this works. I reduce light whenever I see algae and focus on maintaining a stable regimen (e.g. consistent but not excessive fertilization). I see cleaner plants, less algae, better growth. My 4 gallon tank has no fish and so I don't change the water much at all, and it is doing the best.
Interesting point on less water changes. One thing I have noticed is that when I change the water (usually 40% every 10 days) then the tank looks great and algae growth is slow/non-existent for the first 3-4 days. Then I start to see the algae take off. So I believe its telling me that I am running out of something that plants need and when that is out the Algae takes over. If that theory is correct I am not sure how I figure out what that is.
Ammonia and Nitrite are zero. Nitrates usually 10ppm-20ppm by the time I do a water change. Sometimes less. I don't have test kits for anything else so I am happy to go buy test kits for other things if you think its necessary. I am willing to do just about anything to crack the code on this!
On the bright side, my fish (mostly rainbows) look better than ever and that Planted Plus Finnex LED really makes their colors pop!
MattArmstrong
Member
Evad said:
Sounds reasonable. Fertilizers, especially dry fertilizers, are relatively cheap. Going that way has a bit of a DIY flavor to it, and takes some research. I'm trying to convince myself it is no more work than feeding fish.
Evad said:
One thing you might want to consider testing is your general hardness (GH) and carbonate hardness (KH). These are the minerals in the water, and plants need some of them. I recently figured out that one of my problems was that my tap has almost no KH. On top of it being used by your plants, very low GH and KH can contribute to making the water chemistry unstable. The API test kit measures in degrees (dKH and dGH), and it sounds like the acceptable zone for planted aquariums is 3-6 degrees.
-Justin