planting bulb vs cfl help

[Dugsul808]

which of these two light bulbs would be better for carpeting dhg (dwarf hair grass) in my 3 gallon tank. i really dont know to much about lighting. really new to planted tanks.
plant blulb is 60w. the eco smart bulb is 14 watts, 5000k. and ill be using that light fixture that will be sitting right on top of my tank that is 9 inches from substrate to the light. any advice ?

[Gooberfish]

I would not use that Phillips plant light. I used it on some seeds and it only lasted me about 3-4 months being on about 12 hours a day.

The CFL will last WAY longer than the agro light. I'm very confident that the CFL you got will work but don't take my word for it, I'm sure somebody else can chime in on that

[Dugsul808]

Originally Posted by Gooberfish

I would not use that Phillips plant light. I used it on some seeds and it only lasted me about 3-4 months being on about 12 hours a day.

The CFL will last WAY longer than the agro light. I'm very confident that the CFL you got will work but don't take my word for it, I'm sure somebody else can chime in on that

I was planning on getting the natural daylight light bulb but I had these laying around my house so I jut wanted to get an opinion. What's wrong with the Phillips bulb?

[Gooberfish]

For me it just didn't last very long. It also gives off heat which will heat your tank water when it's on.

I also think the CFL will look better. It will for sure last longer. I'm no expert in light either but I am damn certain that the CFL will be the real winner.

[Dugsul808]

Originally Posted by Gooberfish

For me it just didn't last very long. It also gives off heat which will heat your tank water when it's on.

I also think the CFL will look better. It will for sure last longer. I'm no expert in light either but I am damn certain that the CFL will be the real winner.

But your not sure if it will carpet my tank?

[aweeby]

Are you doing a dry start? If so, then blast it with the highest wattage light. (but you need to try keep heat down somehow). If not, both are way too much for a 3g. I'd go w/ a 9w cfl. My high tech 5.5g has a regular 13w 6500K cfl (cost me 3$ at walmart) and that's just perfect. (i have crappy reflectors though.) If you need pics, the link is in my sig. I've been able to carpet HC in that tank. So yeah, you should def be able to get a carpet w/ something like that, assuming you have adequate NPK+trace coverage, (optimally) co2, etc etc.

[Dugsul808]

Originally Posted by aweeby

Are you doing a dry start? If so, then blast it with the highest wattage light. (but you need to try keep heat down somehow). If not, both are way too much for a 3g. I'd go w/ a 9w cfl. My high tech 5.5g has a regular 13w 6500K cfl (cost me 3$ at walmart) and that's just perfect. (i have crappy reflectors though.) If you need pics, the link is in my sig. I've been able to carpet HC in that tank. So yeah, you should def be able to get a carpet w/ something like that, assuming you have adequate NPK+trace coverage, (optimally) co2, etc etc.

Yes I'm doing a dry start. So should I try with a lower wattage or stick with 14?

[aweeby]

For the dry start, you can do whatever. More is generally better, up until the point where the leaves start to get burned/dried out. During dry start of my tank, I had ~75w over the tank. When you flood, switch to something lower. You can use the 14w, but def raise it a couple inches above the surface somehow.

[Dugsul808]

Originally Posted by aweeby

For the dry start, you can do whatever. More is generally better, up until the point where the leaves start to get burned/dried out. During dry start of my tank, I had ~75w over the tank. When you flood, switch to something lower. You can use the 14w, but def raise it a couple inches above the surface somehow.

What will happen if I let it sit in the top of my tank?
Will it melt the Saran wrap?

[aweeby]

1. if your tank is flooded, you'll prob. get algae if you don't raise it higher or reduce the wattage.

2. If the bulb touches, yes. But it's best to raise it some anyway, b/c you don't want to have the tips of the DHG to get burnt from the heat.

[Dugsul808]

Originally Posted by aweeby

1. if your tank is flooded, you'll prob. get algae if you don't raise it higher or reduce the wattage.

2. If the bulb touches, yes. But it's best to raise it some anyway, b/c you don't want to have the tips of the DHG to get burnt from the heat.

Raise it about how high above the tank?

[aweeby]

When you submerse, i'd say at least 5-6" above the surface. For DSM, experiment. if the top of the tank is hot to the touch during photoperiod peak, then raise it some more. depends on the type of bulb you have, ambient temp in the room, length of photoperiod, toughness of the plants, etc.

[Dugsul808]

Originally Posted by aweeby

When you submerse, i'd say at least 5-6" above the surface. For DSM, experiment. if the top of the tank is hot to the touch during photoperiod peak, then raise it some more. depends on the type of bulb you have, ambient temp in the room, length of photoperiod, toughness of the plants, etc.

Okay man thanks for the help
Btw where did you say the links were?

[Hoppy]

That 14 watt CFL bulb should be about 20 inches above the substrate to get 40 micromols of PAR, which is as much light as you need, with CO2 to grow the carpet. Any closer to the substrate and you will very likely have to fight off algae attacks.

[Dugsul808]

Originally Posted by Hoppy

That 14 watt CFL bulb should be about 20 inches above the substrate to get 40 micromols of PAR, which is as much light as you need, with CO2 to grow the carpet. Any closer to the substrate and you will very likely have to fight off algae attacks.

How do you calculate the par?