More "LED for plants" questions
Tropical Fish

Tropical Fish Keeping - Aquarium fish care and resources » Freshwater Fish and Aquariums » Beginner Freshwater Aquarium » Beginner Planted Aquarium » More "LED for plants" questions

More "LED for plants" questions

This is a discussion on More "LED for plants" questions within the Beginner Planted Aquarium forums, part of the Beginner Freshwater Aquarium category; --> I have been reading about switching to LED for the planted aquarium. It does not seem very popular in the freshwater game due to ...

Reply
LinkBack Thread Tools vBmenu Seperating Image Search this Thread vBmenu Seperating Image
More "LED for plants" questions
Old 02-03-2011, 05:37 AM   #1
 
Seanmiller09's Avatar
 
More "LED for plants" questions

I have been reading about switching to LED for the planted aquarium. It does not seem very popular in the freshwater game due to the large number of expensive 3w LEDs it would take to provide sufficient light for any "normal" sized quarium.

I'm wanting to do it on one of my planted 10gs, mainly for expiremental purposes, but also to give the hood a "sleek" profile ie: no large CFL bulge. I would say it is a safe bet that I could provide sufficient lighting for my plants needs.

My questions are:

How many 6500k 1w LEDs would be enough to provide enough light for viewing and photosynthesis to occur?

On a similar note, though more expensive, how many Cree 3w LEDs would provide similar light to about two 7w CFLs? (or would 3w's be a little overkill for such a small area?)

Does anyone know of a retailer that sells 6500k (or close) Crees?

Any input on this subject aside from "just go with t5s" (unless it turns out that plants can't grow under LED then I'm perfectly willing to accept it! ) would be awesome!
Seanmiller09 is offline   Reply With Quote
Old 02-03-2011, 08:58 AM   #2
 
sk8rvendz's Avatar
 
LED Kelvins?

Ive been hunting for the same information for some time now. What is the color of LEDs in Kelvins, lumens etc?

If we could confirm 6500K or so, and figure the lumens, we could figure out how many LEDs are needed for any normal sized tank.

I recently DIY a CFL fixture for my planted shrimp tank. I was looking for good LED data, but only found people very willing to sell LEDs to me.

I guess this is more of a reiteration than a response, but just so you know, you are not alone.
sk8rvendz is offline   Reply With Quote
Old 02-03-2011, 09:56 AM   #3
 
Quote:
Originally Posted by Seanmiller09 View Post
I have been reading about switching to LED for the planted aquarium. It does not seem very popular in the freshwater game due to the large number of expensive 3w LEDs it would take to provide sufficient light for any "normal" sized quarium.

I'm wanting to do it on one of my planted 10gs, mainly for expiremental purposes, but also to give the hood a "sleek" profile ie: no large CFL bulge. I would say it is a safe bet that I could provide sufficient lighting for my plants needs.

My questions are:

How many 6500k 1w LEDs would be enough to provide enough light for viewing and photosynthesis to occur?

On a similar note, though more expensive, how many Cree 3w LEDs would provide similar light to about two 7w CFLs? (or would 3w's be a little overkill for such a small area?)

Does anyone know of a retailer that sells 6500k (or close) Crees?

Any input on this subject aside from "just go with t5s" (unless it turns out that plants can't grow under LED then I'm perfectly willing to accept it! ) would be awesome!

If you intend to use LEDs use the 3 watt not the 1 watt. Also make sure you are willing to go through with this properly. LEDs will cost a couple times more than a spiral compact fixture...
Posted via Mobile Device
Mikaila31 is offline   Reply With Quote
Old 02-03-2011, 06:14 PM   #4
 
Seanmiller09's Avatar
 
Yeah I figured 3w would be the way to go.

I just know I have some CRAZY bright 1w light bars I keep in the trunk of my car in case I need to do some road side fixin'. So just to test, I held one over my 10g and it lit it up pretty well, just only in the area the lightbar covered.... and thats 24 1w bulbs. I estimate I would need like 40 to 60 effectivly light the tank. Not hard, but I think the 3w is a better route, not to mention a much simpler wiring task (if you buy quality drivers).

I really just want to do it for expiremental purposes (plus eliminating the ugly walmart canopy). I also want to get my feet wet so to say, I plan on doing a salt water setup in the near to distant future and figured if I could build a DIY 3w LED system ($200?) that in the long run it would be cheaper since I wouldn't have to change bulbs anualy.
Seanmiller09 is offline   Reply With Quote
Old 02-03-2011, 10:45 PM   #5
 
no LEDs do not run cheaper IMO.... maybe for saltwater, but you can't put the wattage in that hood that you need for SW and use it for FW. LED are also limited to shallow tanks. But for a 10 gallon you could modify your hood to hold 28 watts of spiral compacts for $10-12 and have PLENTY of light. LED fixture will cost you at least $100 and thats DIY. Now spiral compact bulbs cost like $3 each... I'll let you do the math to figure out how long your LED hood would have to last to make up for "bulb replacement costs". You can value in annual bulb replacement, however most don't do this. I run high tech tanks and I replace my PC bulbs when they burn out. Just replaced my first set actually, they ran for 2 years 5 months. At about $15 a bulb thats not that bad really. Its amazing how bright the new ones are though, they will probably cause an algae bloom. Same exact bulb as my old ones.

1 watt LEDs do not work well for plants, so completely forget about them. There is a difference between visible light and photosynthetic available light. What I am talking about is full spectrum, your little road side lights are probably not full spectrum. They emit white light vs full spectrum which is white light made up of multiple color peaks. Plants need red, blue, and yellow light. Buy the wrong LEDs and they can be total crap for growing plants.

Someday I will make a LED fixture, whenever the CREEs stop costing like $10 each.
Mikaila31 is offline   Reply With Quote
Old 02-04-2011, 04:47 AM   #6
 
Seanmiller09's Avatar
 
Yeah I had pratically given up on 1w. The idea still lingers in the back of my mind as just one of those "there has to be a way" impractical ideas.

I have found some cool full LED saltwater setups out there, but like I said, just the "bulbs" and drivers/powersupplies alone are pushing $200. But that is outside this discussion I suppose.

Im a little confused about what exactly color temp is a rating of and how it is determined (where is physics 102 when I need it?!) Color temp and actual nm wave length emitted are related but not entirely dependant upon eachother, correct? **note: this is all my speculation and is not supported by any data** Although, I would think (my uneducated guessing) that when the LED is rated for a color temp of 6500k, the spectrum of light emitted would be close to that of the 6500k fluorescent bulbs or could it be a combination of the wrong wave lengths of the spectrum simulating, visually, the appearance of natural daylight, though missing key spectoral ranges for photosynthesis? If I'm missing the point entierly, please let me know! If thats the case though, could the 6500k fluorescent bulbs we are buying at the hardware store fall victim to the same visual "hodge podge" of non essential wave lengths?

The more I think about this the more I speculate without actual evidence, so I'm going to end there for now. If anyone has any knowlege about color temp in relation to the electromagnetic spectrum please chime in!
Seanmiller09 is offline   Reply With Quote
Old 02-04-2011, 10:20 AM   #7
 
Quote:
Originally Posted by Seanmiller09 View Post
Yeah I had pratically given up on 1w. The idea still lingers in the back of my mind as just one of those "there has to be a way" impractical ideas.

I have found some cool full LED saltwater setups out there, but like I said, just the "bulbs" and drivers/powersupplies alone are pushing $200. But that is outside this discussion I suppose.

Im a little confused about what exactly color temp is a rating of and how it is determined (where is physics 102 when I need it?!) Color temp and actual nm wave length emitted are related but not entirely dependant upon eachother, correct? **note: this is all my speculation and is not supported by any data** Although, I would think (my uneducated guessing) that when the LED is rated for a color temp of 6500k, the spectrum of light emitted would be close to that of the 6500k fluorescent bulbs or could it be a combination of the wrong wave lengths of the spectrum simulating, visually, the appearance of natural daylight, though missing key spectoral ranges for photosynthesis? If I'm missing the point entierly, please let me know! If thats the case though, could the 6500k fluorescent bulbs we are buying at the hardware store fall victim to the same visual "hodge podge" of non essential wave lengths?

The more I think about this the more I speculate without actual evidence, so I'm going to end there for now. If anyone has any knowlege about color temp in relation to the electromagnetic spectrum please chime in!
You are absolutely correct here. This is something I mention every now and then when people say something like 6500K bulbs are better then 8000K bulbs. This is not really true at all, it could be or it could not be depending on the bulb. I pick my more costly power compact bulbs based on their wave lenght spectrum, not their kelvin rating. I'm fine with just going by kelvins on the cheap spiral compacts. When you get into LEDs what will often come up are PAR measurements. This is done by a expensive tool and measures photosynthetic available radiation. You can often find the values for certain bulbs online. I know its out there for the CREEs somewhere.
Mikaila31 is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
36"x15"x15" tank- Questions, wandering about stocking redchigh Beginner Freshwater Aquarium 1 05-22-2010 06:54 AM
"Top Fin Aqua Fern Plants" Trichomanes javanicum IceBerg Beginner Planted Aquarium 3 02-10-2010 01:26 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search



All times are GMT -5. The time now is 05:35 PM.