My new 20g tank came with a: Marine Land Natural Daylight F15 T8 light (18").

The LFS guy recommended that kit, because of the plants I have and the other 20g kit came with an LED light, which he said would kill my plants.

Is the light I have ok for the plants listed in my signature? (They are all mid-low light plants). Pretty sure if I want to go with a larger Watt light, I need to get a larger fixture, (my husband will freak b/c we JUST bought this kit this weekend, lol).

I use liquid ferts' once a week too, and the tank is sitting directly across a small room from sliding glass doors (facing West), so they do get plenty of natural daylight (plus the lighting on the tank).

Thanks for any info'.

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20g Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981
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Im having trouble finding your light,but it should do ok.Will it fit across your tank?And just out of curiosity,can both the LED fixture and the new one go across it?Is the LED a singlebright or a double bright?

Could you post pics?

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http://bountifulbettas.blogspot.com/

"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

Yep, the light goes across the entire length of the tank.

I don't think an LED would fit too... this light takes up the whole space across the top of the glass. And the LED light tank at the store just had a small one, it didn't go across the entire top, (just in the center). Don't know if it was a double bright or not, lol.

Thanks! That puts my mind at ease!

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20g Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981
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I hate to tell ya, but the fish store clerk seems to be confused.

#1. LED lights will in no way kill your plants. Plants can die numerous ways, and the only thing I can imagine the pet store clerk would be referring to is lack of light. If the LED fixture is good enough to be incorporated into the aquarium kit you bought, then I'm 100% sure it will do the trick to feed your plants light, since even a simple T12 shop light fixture will suffice as well.

#2. T8 is a waste of money, in my opinion (keep in mind it is only my opinion, others will differ), because the LED fixture is VASTLY more efficient, and I tend to swear by T5HO or SHO as the best fluorescent fixtures to be had. In a T8, the bulb is too big and strikeback (when light hitting the reflector inside the fixture hits the bulb and is absorbed back into the bulb as heat) will be high since the bulb is so wide in diameter. However, as stated above, it will do the trick, especially for low-light plants. What bulb are you going to use? I'd like to hear the Watt rating, the Kelvin rating, and the brand. Also, does the fixture have a good reflector? The reflector will make as much if not more difference on how much light goes into your tank, as an un-reflected fixture only pumps about 20% of the light's intensity into the tank, with the remaining being absorbed by the fixture and bled off as heat.

Just my thoughts.

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Officially fishless until after the move....tune in later for details!

On my 20g long tank I just used 3 14w spiral pig tail type lights in round clip on reflectors. And those were just placed on an 1/4" square plastic grid (light diffuser for dropped ceiligns {egg crate}).

Tank was plenty bright and plants thrived.

my .02

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fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden

I figured since it's a Natural Daylight bulb and the tank is sitting directly across from sliding glass doors that face West, the tank would be getting plenty of light. (Our betta tank used to be un-light but grew algae like mad because of the daylight it got). How do I find out the Kelvin rating of the light? (It's an F15, so it's 15 Watts).

I called the store today and spoke to a girl in the fish/plant room and she said it should be fine since I've got low-mid light plants (especially since there is lots of daylight in the room - sometimes direct light when the sun is going down), but I will need a better light if I want to get any plants that need brighter light.

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Natural daylight bulbs are generally 10000K for the Kelvin rating - it's the black-body radiation rating and generally refers to the color of light emitted. Natural daylight bulbs are your average everyday bulbs. For plants, you would ideally want a GRO bulb (8000K or lower).

Here's an old post of mine on lighting for a tank:
Lighting Demystified II

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Officially fishless until after the move....tune in later for details!

I'm glad you have found someone that sounds like you trust at a store. Most I would be very cautious before I'd take a recommendation. The easiet way to find better info is through the internet. Not forums per se, but even they have people that actually have done what you're trying to - in most cases. You can't beat experience and most store people don't have much beyond the doors of the store and many don't take the time to learn anything other than how to net and bag fish. I have thought some knew their stuff until I came home and looked up some stuff myself and found out just how full of it they were. Not saying that is your person, but I would be cautious. Don't let that person decide the fate of your tank, without them showing the tanks they say they have at home. I also believe a few use that to get you to trust them.

I've had 2 people from that store say that light is fine and I don't need to buy a different one, (I'd think if they were after money they would recommend a different light...) Plus 2 people here have said they think it's ok (Majerah1 and gtm2007), so I'm definitely feeling better about it. If I want to go to higher light plants, I'll have to get a new fixture for sure because to go with more wattage means I need a bigger fixture..

For low to mid light plants though, I think I'm ok. The tank is pretty bright... and there is lots of day light in here all day... sometimes directly on the tank (at the end of the day).

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20g Heavily Planted http://www.aquariumforum.com/gallery...00&ppuser=8981
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Problem solved: I ended up getting a Lifeglo 15W T8 bulb. It's 6,700K (Recommended for live aquatic plants as well as fish and inverts'.) It looks much brighter than the one I did have on the tank. The other one was just a standard bulb. The guy said it would be ok for a while, but the plants wouldn't 'thrive' and would eventually start to die off. I'm happy now.

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Cool,share pics!

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http://bountifulbettas.blogspot.com/

"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

Will do as soon as the tank is cycled and plants have recovered from the peroxide dip.

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