The Planted Tank Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
39 Posts
Discussion Starter · #1 ·
I just switched up from 270 watts using pc and went to 432 watts using t5s, with 4 actinic and 4 10000k bulbs, which everyone told me was way too much but everything is going crazy! Looks like my plants just exploded with O2 with all the bubbles coming off them now. Oh and the tank looks sooo much crisper than it did with pc lights
 

·
Registered
Joined
·
9,711 Posts
Also, actinics don't do anything for plants. It's be better to go with 6500k bulbs to replace the actinics, unless you want the actinics for fish color.
 

·
Registered
Joined
·
376 Posts
I remember when I put 80 watts of CFL over a 20 gallon, I had great growth too!

...For about 2 weeks, until the plants were so covered in algae they stopped growing completely. :( It got so out of control, I had to tear the whole tank down. Once you get a monster infestation of the really nasty algae (clado, spiro) it is almost impossible to get completely rid of it.

Take the advice of those who have done this before, and pull at least half of those bulbs out. Your plants will still grow like crazy, and you will avoid so many problems in the very near future. If you want better/faster growth, look to your nutrients. (co2/macro/micro.)

And to prove great growth is possible without a ton of light, take a look at this tank. Niko posted it a while back - 90 gallon, with 110 watts of CFL and no co2. So 1/4 the watts you're using, and more like 1/8 the actual light your tank is getting!

Good luck!
 

·
Registered
Joined
·
483 Posts
That is A little to much light, A short photo period would help and running them in sets of 2 up to a 1 hr midday burst would also help. All in all you are using way more power then you need for a nice planted aquarium.

As for to much light, some of Amano's tanks have 150 w metal halides on 20 gal or less tanks that do just fine. Its all about how you want to care for it.

And I would like to see what plants do under 10k lights! "Long term"
enjoy
md!
 

·
Registered
Joined
·
600 Posts
Also, actinics don't do anything for plants. It's be better to go with 6500k bulbs to replace the actinics, unless you want the actinics for fish color.
This is a somewhat false/definitely misleading statement.

Some Actinic bulbs do miss the blue spectrum plants want. Many others hit the band perfectly however, and do supply light for photosynethesis.

In a multiple bulb bank of lighting, actinics (that hit the correct spectrum) are a perfectly good and viable part of a bulb mix. They do still need to be combined with bulbs that emit the red plants want as well, of course.

It is another one of those things people pick up and say without really stating it well..... sorta like saying CO2 chokes livestock, without explaining that it actually is burning gills at high levels, and not actually starving a tank for oxygen. Sorta right in explaining the possible effect (gasping fish), but sorta wrong in explaining why (it isn't choking them, it is making gills unable to process oxygen).


FSM, you do need to have a bank of lights (gotta get the reds too), and you do need to make sure that the actinic isn't off the scale for plants in wavelengths - but no, you can't make the blanket statement that actinics do nothing for plants. That make sense?
 

·
Registered
Joined
·
999 Posts
Is there any data to support this?
From a science point of view....

Actinics is 420nm/460nm wavelength, which enables it to penetrate deeper in water but not is Kelvin rated (mainly blue)

Blue Light is around 420nm in wavelength and penetrates deeper in tanks.
Red light is around 700nm in wavelength and filters out more rapidly.

At a 6,000K rating the ratio between red and blue light is equal. As you move higher say to 10,000K the blue light is higher.

Plants need both red and blue light. Algae tends to prefer yellow/red light so sticking to the 10K bulbs is a common since it limits the red light spectrum. If you used just Actinics you would mainly get blue light and not enough red light to make it to the bottom of the tank to do much of anything for plant growth.

I hope that makes sense....science wise why you need the 6,500K/10K versus the actinic.
 

·
Registered
Joined
·
3,647 Posts
You don't anywhere near 432 watts. Lighting is way overrated. It's all about CO2. Here's my 75 with 108 watts of T5HO.

 

·
Banned
Joined
·
1,241 Posts
This is a somewhat false/definitely misleading statement.

Some Actinic bulbs do miss the blue spectrum plants want. Many others hit the band perfectly however, and do supply light for photosynethesis.
I've seen statements from Tom Barr (I think) that it doesn't matter where in the usable spectrum the light is. Actinics are biased towards the blue, but I would imagine that for the majority of bulbs, for the majority of the spectrum they are supplying light that is useful to the plants. They're just not as good as any of the plant-specific bulbs and they're not pleasing to look at.
 

·
Registered
Joined
·
21,012 Posts
From a science point of view....

Actinics is 420nm/460nm wavelength, which enables it to penetrate deeper in water but not is Kelvin rated (mainly blue)

Blue Light is around 420nm in wavelength and penetrates deeper in tanks.
Red light is around 700nm in wavelength and filters out more rapidly.

At a 6,000K rating the ratio between red and blue light is equal. As you move higher say to 10,000K the blue light is higher.

Plants need both red and blue light. Algae tends to prefer yellow/red light so sticking to the 10K bulbs is a common since it limits the red light spectrum. If you used just Actinics you would mainly get blue light and not enough red light to make it to the bottom of the tank to do much of anything for plant growth.

I hope that makes sense....science wise why you need the 6,500K/10K versus the actinic.
I have yet to see any good test results that demonstrate that actinic lights don't help plants grow. Logically I agree with much of what you said, but I don't think the testing has been done, or at least it hasn't been widely reported on forums. Perhaps that is because most people find that actinic light makes a planted tank look ugly. So, they don't really care what it might do for the plants.

The loss of light intensity versus water depth is very slight for the tank depths we normally use - up to 24 inches or so - no matter what the color of the light. And, that is true for reef tanks too. But, corals generally grow in deeper water than that, so they do get more blue light than red light. People use actinic lights on reef tanks primarily because they like how it looks.

Algae grow where they can get light. I know of no comparative test results that show a preference for any particular light spectra by algae in aquariums.

Most light specs are in lumens, which are biased to match the human eye sensitivity, but human eyes are not very sensitive to red light. So, the PAR intensity from a light with a given spectra isn't likely to match what your eyes tell you, or what lumens based spectral intensity charts show.
 

·
Registered
Joined
·
999 Posts
I wasn't saying that actinic lights don't help plants grow just that they only supplied the blue light that the plants need and not the red light. Chlorophyll absorbs at the two wavelengths, red (620–750 nm) and blue (450–495 nm). Green (495–570 nm) is not absorbed (for the most part) and is reflected (hence why MOST plants are green).

The blue spectrum is fairly close to the green spectrum so you have a chance of loss unless you're on the low end....plus some actinic are rated at 420nm (Violet) so you are below blue there.

As for Algae I found this interesing tidbit on Google.

"Red wavelengths are absorbed in the first few metres of water. Blue wavelengths are more readily absorbed if the water contains average or abundant amounts of organic material. Thus, green wavelengths are often the most common light in deep water.

Chlorophylls absorb red and blue wavelengths much more strongly than they absorb green wavelengths, which is why chlorophyll-bearing plants appear green. The carotenoids and phycobiliproteins, on the other hand, strongly absorb green wavelengths. Algae with large amounts of carotenoid appear yellow to brown, those with large amounts of phycocyanin appear blue, and those with large amounts of phycoerythrin appear red.

At one time it was believed that algae with specialized green-absorbing accessory pigments outcompeted green algae in deeper water. Some green algae, however, grow as well as other algae in deep water, and the deepest attached algae include green algae. The explanation of this paradox is that the cell structure of the deepwater green algae is designed to capture virtually all light, green or otherwise. Thus, while green-absorbing pigments are advantageous in deeper waters, evolutionary changes in cell structure can evidently compensate for the absence of these pigments."
So in the end if you know what type of pigments your plant has you can tailor the light to it.
 
1 - 14 of 14 Posts
Top