6500k vs. 12000k for plant growth.

[pleechford]

Hey guys, I have a question for y'all. I have a 25g tall with t5ho x2 24 watt and currently have a floramax and a 12000k in it. I am trying to grow glosso but it's just growing vertically. I guess what I'm trying to say is that is my 12000k pretty much pointless for my plant growth? People are telling me to get a 6500k bulb to replace my 12kk and my glosso should grow horiz. And my plants will do so much better. Thoughts? Suggestions?

 

[Daxhua]

I've read people using 8000K - 12000K lamps on deep tanks to get enough all the way to the bottom. I think the 6700K natural daylight bulbs may emit more usable light spectrum for plants to grow that's why people (myself included) prefer them for their planted tanks. I've also read that with the higher temp bulbs you tend to get more vertical growth out of your plants and with lower temp bulbs like 6400K - 6700K the growth tends to stay low or horizontal. Careful with those high temp lights because if you don't have a proper nutrient balance or CO2 injection in your tank you could get a lot of algae growth.

 

[pleechford]

Ok sweet! That's what I'm experiencing is some algae growth. I am getting a lot of light at the bottom of the tank but it's just not usable I assume for the glosso. Thanks for your help!

 

[aqua_chem]

I don't think it's accurate to say that 12000K isn't doing anything for your plants. Who makes your bulb?

 

[Daxhua]

I agree with aqua_chem I'm not suggesting that you can't get good plant growth with higher color temp bulbs, what I am saying is that there's a lot research that supports that plants grow better and faster with bulbs in the 6400K to 6700K temp range. The higher the color temp the closer you get to blue, the lower the color temp the closer you get to yellow and red.

 

[pleechford]

I don't think it's accurate to say that 12000K isn't doing anything for your plants. Who makes your bulb?

True lumen. They are the bulbs that came with my current nova t5ho "fresh water" set up. Yeah its probably not an accurate statement. But I'm assuming that it is not optimal for plants?

 

[pleechford]

I agree with aqua_chem I'm not suggesting that you can't get good plant growth with higher color temp bulbs, what I am saying is that there's a lot research that supports that plants grow better and faster with bulbs in the 6400K to 6700K temp range. The higher the color temp the closer you get to blue, the lower the color temp the closer you get to yellow and red.

Okay. That is what I thought. I just want my glosso to carpet and my rotala colorata to be pink instead of green. From what I'm thinking they both has to deal with light because I am dosing ferts in the water column and in the substrate. The only thing I can think of is light...

 

[Daxhua]

I still don't know a lot about plants but I learned that red plants need iron, and for plants to carpet your substrate your prob gonna need CO2 injection.

 

[pleechford]

I still don't know a lot about plants but I learned that red plants need iron, and for plants to carpet your substrate your prob gonna need CO2 injection.

I have co2 injection at above 30 ppm I'm assuming since my DC is almost yellow. Co2 cant be an issue. And my root ferts have a good amount of iron.

 

[Daxhua]

Ok maybe it is your lighting. Blue does tend to favor algae growth maybe that is why you're having some trouble with your glosso and rotala.

 

[pleechford]

Tank shot and glosso. Glosso is in between 1"-2"

 

[mfdrookie516]

I've found geisemann aquaflora and midday bulbs (1:1 ratio) seem to be the best combination IME for plant growth. Not saying other bulbs aren't good, but the aquaflora bulb is engineered specifically for plant growth, and they did a fine job doing it. Well worth the small investment IMHO

 

[pleechford]

I've found geisemann aquaflora and midday bulbs (1:1 ratio) seem to be the best combination IME for plant growth. Not saying other bulbs aren't good, but the aquaflora bulb is engineered specifically for plant growth, and they did a fine job doing it. Well worth the small investment IMHO

That's what I've heard as well. Unfortunately I am financially unable to get geisemann since they are relatively on the high priced end for bulbs. Since I have True Lumens brand of the aquaflora bulb I'm really considering the GE Starcoat 6500k bulb . It could possibly make the same combo for a cheaper price??

 

[mfdrookie516]

Where are you shopping? Aquacave is where I've always purchased my bulbs for fw, and some for sw. They don't charge oversize shipping, and the geisemann bulbs are only $5-10 more than the GE's... If that $5 to $10 is a make or break thing for you, then the GE will be fine, but speaking from experience, it's well worth the extra every year for the geisemanns. Just be glad you don't have 6 or 8 to replace!

 

[pleechford]

Okay thanks! I am going to really do some thinking about it. Do you think they would definitely help carpet my glosso from my bulbs that I currently have?

 

[aqua_chem]

I agree with aqua_chem I'm not suggesting that you can't get good plant growth with higher color temp bulbs, what I am saying is that there's a lot research that supports that plants grow better and faster with bulbs in the 6400K to 6700K temp range. The higher the color temp the closer you get to blue, the lower the color temp the closer you get to yellow and red.

I call BS on this. Temperature is an extremely poor metric for bulbs. It is literally judging a book based on its cover. You need to consider the ENTIRE spectrum, not just what the color appears to be. The reason the blue bulbs are bad is because the spectrum is lumped entirely in the blue without any red or green. I bet that 10000K+ bulbs that are designed for FW have sufficient green/red light to grow plants.

 

[aqua_chem]

Tank shot and glosso. Glosso is in between 1"-2"

Amateur.

 

[pleechford]

Amateur.

Now that is some tall glosso. Beautiful reds might I add

 

[mfdrookie516]

Okay thanks! I am going to really do some thinking about it. Do you think they would definitely help carpet my glosso from my bulbs that I currently have?

I think they'll cause more growth than the bulbs you have... maybe some better color too... but what you have will work. Maybe wait until you need to change bubs before you upgrade?

 

[pleechford]

I call BS on this. Temperature is an extremely poor metric for bulbs. It is literally judging a book based on its cover. You need to consider the ENTIRE spectrum, not just what the color appears to be. The reason the blue bulbs are bad is because the spectrum is lumped entirely in the blue without any red or green. I bet that 10000K+ bulbs that are designed for FW have sufficient green/red light to grow plants.

So what do you advise to be the best t5ho bulb that'll help being out reds in this such as rotala and assist is the horizontal growth of glosso?