Low lighting question

[Blacksteel]

I'm planning on starting up my first planted tank and I have a 20 gallon long tank. I plan on having low light because I'm not planning on using any fertilizer or CO2. I plan to keep easy low light plants as I'm new and want to start slow (java moss, java fern, maybe some swords, and hornwort). I have two lights right now and I'm curious as which one would be better.

I have just a standard florescent tube that comes standard on most tanks. It is a T12 20 watt pink bulb.

The other light fixture I used on my reef setup that I broke down and it is a Quad T5HO, a total of 96w.I know the T5HO is obviously stronger but Is it too strong and I don't really want to use it as it puts off a lot of heat. Plus I think i remember reading that stronger lights will require more fert/ CO2 for the tank, but I'm not sure if this is true.

Thanks for your help!

 

[rich311k]

96 watts would put you into the ridiculous area. 20 watts is going to be low light. If you want a sword or two you want to shoot for around 2 watts a gallon. Does the quad have separate on/off switches for the bulbs?

 

[Blacksteel]

Ya I can make it 48 watts. By leaving only two lights on. Will that be medium or low? And would the 20 watt fixture be able to sustain those plants or is it probably not strong enough?

 

[rich311k]

I would go with the 48 watts on an 8 hour cycle, that should give you what you want. i fear the 20 is just too little.

 

[Mr. Limpet]

I'm planning on starting up my first planted tank and I have a 20 gallon long tank. I plan on having low light because I'm not planning on using any fertilizer or CO2. I plan to keep easy low light plants as I'm new and want to start slow (java moss, java fern, maybe some swords, and hornwort). I have two lights right now and I'm curious as which one would be better.

I have just a standard florescent tube that comes standard on most tanks. It is a T12 20 watt pink bulb.

The other light fixture I used on my reef setup that I broke down and it is a Quad T5HO, a total of 96w.I know the T5HO is obviously stronger but Is it too strong and I don't really want to use it as it puts off a lot of heat. Plus I think i remember reading that stronger lights will require more fert/ CO2 for the tank, but I'm not sure if this is true.

Thanks for your help!

The pink bulb should say what the "K" value is. 20w would be my choice with a 6700K bulb.

The SW fixture would be high light to say the least, but one 10kK and one Actinic with nothing in the the other 2 slots would make the tank look bright and not force you into high light situation IMO.

BTW, here's a great site for plants: PlantGeek.net - Your Aquatic Plant Resource

 

[Blacksteel]

Thanks I forgot what that site was called and I couldn't find it. Also the light says K5 on it? I dont think that's right though lol

 

[jetajockey]

I think for your particular needs a single t5ho light would work best. A pair of t5no would work also but might be a little high, 20Ls are not tall at all, so it doesn't take much lighting to put you over the top.

 

[Blacksteel]

I'm looking up the light bulb online and it really doesn't say the K it says it 500 lumens?

 

[Blacksteel]

Ya I'm planning on selling the T5HO for around 50$ is there any light fixture that would be good for my setup around that price?

 

[mfdrookie516]

You can use the light fixture you have... Either 2x24w with co2 injection, or a single daylight (somewhere between 6500k <yellowish> to 10,000k <my preference because it's much whiter>) and an actinic would give you good light without the need for co2.

 

[jetajockey]

depending on the brand you might be able to get more than that for it.

Unfortunately there aren't a ton of single t5ho fixture options out there. There is a cheap dual bulb oddysea fixture on ebay, which might be a little overkill, but would be cheap. I got my 4ft single t5ho fixtures (hanging type) on ebay also for i think around 40-50 each but they won't mount on the top of a aquarium without rigging something up or hanging them.

Using 2 out of 4 might work if you like the look of actinics. I don't like the way they look with different shades of green personally, but in nonplanted tanks I like them. I'm still unsure about their actual effect on plant growth/algae growth apart from being somewhat useless, still not confirmed on how useless though.

 

[Blacksteel]

Yeah I figure I should probably just use the T5HO because then if I ever want to upgrade I can pretty easily. I already have a 10kK and actinic in the fixture so that is probably just the easiest option. I just wouldn't mind using that 50$ to buy plants but then again they might die with the 20 watt light. Thanks for all your help!

 

[Mr. Limpet]

Thanks I forgot what that site was called and I couldn't find it. Also the light says K5 on it? I dont think that's right though lol

Best I could find is a 20w, t12 outputs 4100K, which isn't bad for your tank and still keeping it low light.

F20T12/CW/ALTO - 20 Watt, 24 Inch T12 Cool White Fluorescent Bulb | Bulbs.com

 

[Blacksteel]

I actually found out that it is 3400K (pink bulb). Would that be able to support the plants I am interested in though?

 

[Mr. Limpet]

Well would you say that the 4100k would be able to support the plants I am interested in though?

It's on the low end of the spectrum, but it might.

I have a 55w PCF 10kK/blue on a BW 29g planted and I really like the look of the white/blue combo. Like you said, you have the 10kK/Actinic bulbs already so I'd suggest trying that since it won't cost you anything. 1x24w @ 10kK will be good for the plants and the 1x blue bulb is more ambiance than useable light for the plants.

EDIT: Can't find to confirm, but I read somewhere that 2600K to 10kK will work.

 

[Blacksteel]

Okay I'm probably just gonna go with the T5 because it will also make the plants grow more. Thanks for all your help and the fast replies!