Lighting

[swampfox25]

Ok I know this is probly on the site but I couldn't find it. What is a good rule of thumb for lighting compared to size of tank. I am setting up a 29 gallon and want to put a nice amount of plants in it. Thanks.

[punch]

Depends on the plants you want, 1-1.5 watts per gal. low light,
2-2.5 medium, 3- + high. Of course thats just a genaral rule.
so for a nice midium light plant tank, shoot for around 60 watts.
The higher light you go, you have to start thinking about injecting
co2 and ferts.

[superjohnny]

Two 36w power compact flourescent lights would work great. So would one 55w.

check out www.ahsupply.com for a DIY kit, bigalsonline.com or hellolights.com for a light & fixture.

[carpguy]

Folks use watts per gallon or wpg when talking about lighting for planted tanks. The sort of easy general scale kind of way that I think about it runs like this…
< 1 wpg = not really enough.
1-2 wpg = low light.
2-3 wpg = moderate light.
3+ wpg = bright or high light.

They're gradations. There's not a huge difference between 1.9 and 2.1. And they're approximate… DJLen recently wrote in another thread that he thinks of 1.5 watts as being the bottom end of the scale. Maybe that pushes the steps up a little.

There are a few other factors to consider: smaller tanks need higher wpg… you can't grow plants in a water glass with a flashlight, there is a certain minimum amount required. Water filters out light… for a deep tank you may want to bump up a little bit. You'll want to take a look at some sort of CO2 supplementation once you start to get into moderate light or higher. Not really needed for low light.

I have a 30g with a pair of 36w CFs from AH Supply (http://www.ahsupply.com) about 2.4 wpg, and I'm very happy with them but wouldn't mind it a little brighter.

The basic problem with a 29g is that its probably 30" wide, and there aren't really a lot of lights that come in that size. If you want to go with an enclosed canopy you could just install the two at a slight angle or set them a little offset. Or you could install a 55w dead center: the 3" space to either side isn't that significant. Not ideal, not bad. All-glass's 30" high output is a 55w with space to either side. Their 36" HO is a pair of 55s offset.

1 55w would give you about 1.9 wpg, towards the high end of low.
2 x 36w would give you about 2.5 wpg, pretty solid moderate and a nice level IMHO.
2 x 55w would give you about 3.8 wpg, which is bright.

Or you could work out some configuration of NO lights.

[swampfox25]

Well my tank came with a 20 watt light (I think on the back of the hood it says it) I planted about 3 swords and some mondo grass. I hope they wont die on me before I can get better light because i dont have the $$ right this second. The tank does look pretty bight though. but my wpg is only 20 watt / 29g =.689wpg is that right?? if so How long will the plants be ok for? I bought fertilizer incase they turn yellow but I didnt want to use it unless I had to. I have c02 tablets as well until I can get an injector and time.

[swampfox25]

Ok guys I found a cool kit that is a retro-fit. I had to gut the housing for my 20 w. I then had to hook up the wireing and screw the reflector and new bulb to it. The bulb is a Smart Lamp 10,000k Premium Daylight and Ultra Actinic side by side. It is a Power compact bulb with 65 w. That should give me 2.24 wpg that should be enough?? I am running the light 12 hours on and 12 off. It is really bright and has a blue look to it. Makes some of the rocks look really cool. The neons look cool too. Thanks

[GulfCstAquarian]

While the Actinics do make a very cool effect (especially on Neon Tetras!) the plants aren't going to be benefitting from it very much. It's a bulb designed for growing corals in reef tanks. Exchange it with just about any daylight PC bulb (5500-6700K) and you'll be a lot better off.

[swampfox25]

So will this light not work. I really dont have the $$ to change it right now. Will my plants die??? Do i need c02?? Thanks

[10_Gallons]

The swords will probably hang on for a while.. maybe for a month or two (don't remember, but I foolishly bought some when starting out with insufficient light too ;)), but they need a lot of light, and what you've got isn't even sufficient for many low light plants. Unfortunately, they tend to sell new aquariums with lighting that isn't suitable for plants.

CO2 and fertilizer aren't really going to help if you don't have enough light.

I suggest you wait until you can afford it and get really good lighting, then you'll be able to plant whatever you want and you will get much faster growth.

[swampfox25]

The lady at the LPS told us this is a great light for fresh water plants?? It is a full spectrum natural daylight. I duno I swear everything has greened up alittle since I had the 20w bulb. Do they sell light bulbs that will work on my PC fixture?

[swampfox25]

Nobody?

[swampfox25]

Ok I talked to the pet store again and I can not return the light. But she showed me the graph of a 6700k and a SmartLight and they are exactly the same other than one has higher in the blue

http://drich007.no-ip.com/images/67.jpg

That is the 6700K bulb you guys are taking about


http://drich007.no-ip.com/images/sl.jpg

This is what I have. I know the blue spectrum is high but you think it will work for the time being? I think I was telling you guys I had a different bulb (just a 10,000K antic) but it is a 10,000K Smart Light. Sorry for the mixup and thanks alot for your help. I have just been stressing over this...

[caffeine]

I just did some searching, and I believe the above posts were correct. The SmartLamp by Custom Sealife is a 50/50 bulb. Half of the bulb is 10,000K daylight and the other half is Actinic.

swampfox25 - When you look at the bulb when it is turned on, is one half of the bulb blue and the other half is white?

[GulfCstAquarian]

1) I wouldn't put too much confidence in marketing data like those graphs.

2) If those spectral graphs do accurately represent the distribution of light output, then the smart lamps is producing almost half of its output in the blue region. (The area under the curve in the 400-450nm region is greater than the rest of the spectrum). While plants do greatly utilize both blue and red areas of the spectrum, this is an imbalanced bulb and will provide excess blue light and inadequate red light for plant growth.

It's not the end of the world, but your LFS should read up some more on plant photosynthetic needs before recommending a bulb they've got in stock.

[swampfox25]

OK thanks for the help