Xpost, Plant light bulbs?

[sandwich]

Background- I have a 40 gallon long tank that is lightly planted (3 plants). I've been debating about a light fixture for a while, and I finally decided on a shoplight from home depot.

My question is:
I went to petco, and all they had were aquaglo etc. (hagen?) in t10. From all the information i could find, those aren't compatible with t8 fixtures. I ended up getting a t12 setup from home depot, which I am thus far pleased with, but can a t10 bulb fit in a t12 setup? They are the same wattages. I have a 40 watt t12 plant and daylight plus setup. The tank looks pretty good, but is this a good setup?

What can be done with the whole t8 things? I've heard they're even better than the big bulbs. Do they have to be overdriven?


Will this help my plants to grow, or should i run a second daylight bulb? The plant bulb is pinkish.

 

[TonyN]

I dont know if a t10 wil fit in a t12, but it you only have one 40 watt bulb, in a 40 gallon tank, then that is really not enough light to grow plants. There are a few low light plants that will grow, but most plants require 2 to 3 watts per gallon. So you would need two or three 40 watt bulbs to really grow stuff.
Also, what they call "daylight" bulbs, usually arent really full spectrum bulbs. They are usually around 3500k, when what you really need is about 6700k. See if you can get a rating on the bulbs you are using.
Unfortunately, if you're serious about growing plants, there really isn't any cheap way to go about lighting. It's expensive, but you are better off with 6700k bulbs that are made for aquariums, and with enough wattage.

 

[sandwich]

i have two bulbs, both 40 watt t12s.

One is the Daylight Deluxe and is rated at 6500k.

The other is a plant and aquarium, and it's 2700k, I think. Can't really understand why it would be so low, but I thought I would try it.

Should I return the plant and get another Daylight bulb? They had daylight and Daylight deluxe....this is supposed to be whiter and has a higher color temp. The daylight is said to be full spectrum and 5000k

 

[TonyN]

Yeah, I would take that one back and get another 6500k bulb. That would give you 80 watts of 6500k, or two watts per gallon. That should be enough. Also, if you wanted to add more later, you could get a cheap incandescent fixture, and put in some of those new screw-in compact fluorescents. You can get those in 6500k too.

 

[happychem]

Wattage over spectrum.

Yes, a T10 will fit either T8 or T12 fixtures. All three bulbs have identical pins. The catch is that T12s will not run on magnetic ballasts. T8 bulbs are more efficient that T12s, while they are lower wattage, they actually put out more light. The watts per gallon "rule" is a benchmark to be used carefully. It only applies for medium sized tanks with T12 normal fluorecent bulbs.

I'm willing to bet a fair sum that your 'plant and aquarium' bulb looks pink. 2700K put out a lot of 'red' light, which is good for plants and I'd be willing to bet it's great for houseplants. Unfortunately, red doesn't travel very far through water, so your lower leaves may suffer. If it's the GE plant and aquarium, I was running one a few months back, bottom leaves on my sunset hygro were always dieing, top ones were doing great. Mind you, it was also on a faulty ballast, so take that anecdote for what it's worth.

 

[TonyN]

Happychem - If the watts per gallon rule only works for medium size tanks with t12 bulbs - then how would you figure out how much wattage I need for a 40 gallon breeder, using compact fluorescents?

 

[sandwich]

Wattage over spectrum.

Yes, a T10 will fit either T8 or T12 fixtures. All three bulbs have identical pins. The catch is that T12s will not run on magnetic ballasts. T8 bulbs are more efficient that T12s, while they are lower wattage, they actually put out more light. The watts per gallon "rule" is a benchmark to be used carefully. It only applies for medium sized tanks with T12 normal fluorecent bulbs.

I'm willing to bet a fair sum that your 'plant and aquarium' bulb looks pink. 2700K put out a lot of 'red' light, which is good for plants and I'd be willing to bet it's great for houseplants. Unfortunately, red doesn't travel very far through water, so your lower leaves may suffer. If it's the GE plant and aquarium, I was running one a few months back, bottom leaves on my sunset hygro were always dieing, top ones were doing great. Mind you, it was also on a faulty ballast, so take that anecdote for what it's worth.

Thanks for the info, more q's though:
I have a 40g long, which is 16" deep. The bulb does indeed look pink. Should I keep it or return it? I do recall hearing something about them being discontinued due to lack of effectiveness, but i've got nothing concrete.

#2, I think my t12's are on a magnetic ballast, that's what the sign in home depot said, I'll have to check the box. Did you mean t10's won't run?

I'll have to take some pics, thanks for the help!

 

[biogirl361]

can you put a regular plant light on an aquarium hood? i mean for growing plants in a 20 gallon, that is like 80 watts of light i need, that will cost a hundred bucks if i try and buy aquarium bulbs. that is rediculous. you can get a 120 watt regular plant light for 5 bucks.

 

[happychem]

Tony, 40g is a 'medium sized' tank as far as I'm concerned. What I mean to discount is more 15g and under tanks which need more wpg's to saturate the plants with light. Since the wattage refers to the amount of energy used and not the light emitted, the wpg numbers are just rules of thumb and ways to talk about light intensity in a more understandable manner than the light energy emitted, which isn't listed on any bulb. Note that when bulbs report lumen output, it is the light intensity as viewed by the human eye, plants are interested in a different spectrum. For pc bulbs, follow the wpg 'rule' but just be aware that you're putting in more light. So err a little on the less light side.

Sandwich, return the bulb if you can, but if you can't don't be too worried. Like I said, it was only the lower leaves that suffered. My 33g is 18" deep, minus a few inches for substrate. So probably roughly 16" to the bottom of the stem above the substrate and it was about the bottom 4-5" that were really suffering. Watch your plants and if you figure they're suffering from the light, get a new bulb.

#2 - Yes, if you bought one of their shop light style fixtures, it's a magnetic or tar ballast (I'm not entirely clear on the difference, if there is one).

Sorry, I was in a big hurry this morning. I meant to say that T12's won't run on electronic ballasts. T10s should run on both, the box that xxx-Glo bulbs come in actually makes a note of saying that the bulb will run on both electronic and magnetic ballasts.

biogirl, if you're talking about the fluo. hoods, then yes, most "aquarium" hoods are just fancy looking magnetically ballasted fluorescent hoods.

 

[biogirl361]

i was talking about normal terrstrial plant lights, like you find in the garden section next to the regular houseplants. i was wondering if i could just put one of those in the aquarium hood fixture, because it seems like you could get 4 times as much wattage and the same spectrum for a lot cheaper than the ones specially marketed for aquariums.