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37 Posts
Discussion Starter · #1 ·
Help me !!! I have been reading, reading, and reading the past hour. Hoping to find some form of solution, to getting the right type of light for my new 20 Gallon tank. Maybe i am just confused, or just making it harder then it really ought to be. Now i get the WPG rule which works for tanks, that are between 20-70 gallons which is fine.

Here comes the fun part about kelvin ratings, to wattage, and etc. I know from reading over and over, that plants photosynthesize best between the range of (5000-6700k) spectrum. And that you should be looking for peaks in the blue, and red colors which is beneficial for plants. Blues tend to be on a 475 nm scale(ie. nm = nano meter), and reds tend to be 650-675 nm scale for plants to grow at their best.

I still have no clue where 10,000k lights come into play, aside from being used in marine aquariums. But have no clue how it will be benefit the plants in growth, unless certain light models emit in this light in the blue n red range. And just giving it a preference on color choice. But then again ive read on threads, where people can successfully grow plants under these lightings. But are there certain plants that, benefit with such lights? But this 10,000k thing is just a side note.

So given the knowledge to what i have read, i would need the following light setup:

-40 watts of light based of the WPG rule (2/wpg)
-light in the range of 6500-6700k range.
-with good peaks in the blue and red's based of the labelling on the product id be buying.

Now i know light also is a factor for which plants, a person will be growing as i plan on doing low-medium light plants. B/c we all know as much as low light plants are neat, you get more option of species of plant if u just take an extra step to higher lighting. I plan on keeping the typical low light plants, like (anubias, j.fern, j.moss, etc...) just to name a few. Then some moderate light plants as well, that would like (water wisteria which i already have, ambulia, Hygrophila polysperma, dwarf sag, etc.....). And few others...

Here is the fun part. The stock lighting that i got with the tank is a 20watt 24" Power-Glo flourescent light bulb with a 10,000k rating. It appears on the blueish with tinge. It means nothing to me in lamen terms. Now i can stick with what i have, but growth wont be as ideal. I also know that higher lighting you have, the rapid demands are in the supplementation area. Hence i figured i keep it simple keep it low-moderate lighting, and possibly provide the suplementation through flourite as my substrate. If need be as a last resort setup a diy co2, and liquid dosing which i have been doing moderately with Flourish:Comprehensive.

I went to the LFS's to check out lighting, i couldnt find lighting up to 40-50 watts that would fit under my light canopy. The staff suggested that i get a new canopy, that has dual light strips. I checked the price, and i ran out the store. Then i googled more found out you can get 24" high output flourescent bulbs, but i didnt see it in any LFS's that i went into. Then i aint sure if the HO lights would be compatible, with the light canopy i have.

Or worst comes to worst make my own DIY Hood, hopefully with a budget of $50 dollars with the finished product.

I think i am done

Insert Input Below........Please and Thanks :) :) :)

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37 Posts
Discussion Starter · #3 ·
Frankly I dont even know, why i am so gun ho about this whole lighting matter. Don't even know, what trouble it might brew up trying to to this whole 2/wpg. Guess i just like the look of a planted tank, and having to more selection plants than the i normally would.

Anyhoo I was just casually visiting Pet Smart, i noticed a light/canopy kit for $25 dollars. Basically it comes with T8 lighting, just like the light hood i have right now with a 24" - 20 watt bulb. So that all adds up to 40 Watts...... :D. I still got the receipt if i need to return it !

Aside from that not really sure which are more beneficial interms of lighting type, whether it be T5,T8,T12's ?

Also can these light types, be interchanged between any fixtures ? Maybe not i guess since the size, would not match up to the fixture. lol i think i might be wrong, but i think that is what makes to what read last.

Also when one decides to purchase light, to place under their hood. What are some things a person should be looking for, interms of specifications of the lighting.? Like full spectrum scale? And type of spectrum meaing..... (5000k - 18,000k) ? Lux Rating ? Lumen Ratings?

Guess these should have been my first, educated questions i should have asked initially.

Last but not least what would you do if, you were in my shoes in making a decision like such? Also with some plants that i listed.....?

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Try to find a simple t5 fixture. The LFS's around my area sell a basic 2x24 watt fixture for around 50 bucks. I had this fixture over my 20 high and grew most medium light plants easily. I switched to the geismann bulbs and my bylxa is turning pink!


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37 Posts
Discussion Starter · #8 ·
Well what my main goal is to turn my 20 gallon tank into a jungle, more like an aquascaped jungle. lol. As far light is concerned at the moment, i think i will sticking with the current light fixture i have. If anything replace the 24" T8 Power-Glo Fluorescent bulb (ie. i think it is 18,000k) which came with the tank, to some other type of light someone can recommend that be beneficial to some the plants i listed.

But at the moment i only dose my tank with Flourish:Comprehensive, and nothing else. Though someone suggested that i should add Flourish:Trace as well, but when i compared both on the website didnt notice much difference. Could be wrong ! lol.

Though i do plan on setting up a "diy co2" within the next couple of days, just unclear about few things about it. Other then that i think it is a no brainer. Hopefully. *Crossing fingers* Also if i was to shell out money, id just shell out on good quality substrate for plants.

The only i dont want to get into, as money doesnt grow on trees. Is go all fancy with planted tank, meaning doing complicated dosing etc etc...

Just keep it simple to moderate. That is all. I like variety in plants, guess that is what i am getting to. Doesnt matter wether it is slow growing, to medium rate growing plants.

Hope that gives a decent ball park where i stand with all this. And hope someone can help the lil tyke over here :lol:

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1,675 Posts
the light bulb only goes so far itself.
A GREAT light bulb will be mediocre with a poor or no reflector and a descent light will be GREAT with a quality reflector.

Because T5's are smaller and that you can get GREAT high polished multi bend reflectors and also that T5 HO's are over driven, they are about the best fluorescent option going.
However, for a 20 gal tank, it would certainly be overkill unless you want a challenge or a SW reef (which many will argue could need much more light)

Also, you might have mentioned above, but I didn't catch it if you did, do you have a 20 tall or a 20 long.

IMHO coralife makes T5 NO light fixtures (24" for a 20 tall and 30" for a 20 long) and two of them over either of those tanks would be perfect.

I like them better then the coralife PC fixture for several reasons.

One is they are sleek and super low profile, you hardly notice them.
Two is they run super super cool, so heat is not much of an issue.
Three is the color. They come with one 6700K (or 6500k, not quite sure) bulb and one Pink bulb (don't remember the K rating, might be around 8000k) which to me makes the tank stand out.
I love the color the pink bulbs add. It adds light without adding too much brite. It really gets your plants going, the greens are super green and the reds really stand out. And it makes the tank look really natural to me, not so much artificial like you see sometimes, especially in SW tanks (not to bag on SW, I love them also, but some look so UFO to me)

So IMO, these are the best bet for you
Two of them
or if you have a 20 tall (24" instead of 30")
for $2 less get these

Now you won't really go wrong if you get the other coralife fixture, PC is fine and for your sized tank, it will work just fine.
They even make a PC bulb that is split with 1/2 white and the other half Pink.
I don't know if they sell it in the box or if you have to buy the bulb separate.
But if you do go PC instead, you might consider this one.
The thing about this is it comes with a 1 watt moon light which IMO is a great addition.
It is cool to see the tank lit up dimly at night.

One thing to consider about the Current I pointed you to is that it does ONLY come with a 50/50 bulb, and that is 50/ white and 50/ actinic (blue) which is really ONLY for SW tanks.
The blue is not beneficial to plants at all that anyone can really tell you about.
And that adds cost to the whole thing.

However that is the only option of any listed that comes with a moonlight, so if you like that idea, that is the way to go, of the options you have been linked to that is.

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1,675 Posts
On the CHEAP, you can go with this. Comes with two PC bulbs AND the moonlight.

Not the best quality, but many do like them, especially Reefers really seem to go for these fixtures.
I think because they make affordable MH lighting fixtures and that really helps when going SW.
Many of the MH light fixtures that Reefers NEED run in the thousands and you can get MH from these guys comparable (in light output, not necessarily quality) for several hundred, and that is where they get love from the SW community.

Anyway, you can get the 1/2 white 1/2 pink bulbs with the fixture for no extra charge if you specify when ordering.

This comes with two bulbs and two switches, so you don't have to run both, and that means you already have your next bulb for when the first one burns out.

Or you could run one for 1/2 your photoperiod and the other for the other half.
This will make the bulbs last twice as long but it will give your tank an effect of getting light from different angles like plants do in nature as the sun passes overhead.
Not a necessary at all or a huge deal, but fun if you want to go that route.

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Well what my main goal is to turn my 20 gallon tank into a jungle, more like an aquascaped jungle. lol. If anything replace the 24" T8 Power-Glo Fluorescent bulb (ie. i think it is 18,000k) .
Yes it is 18,000k. How long have you had that light over the tank? I was thinking it would be a good combination with the Life-glo lamp for my 29 low light tank.

Oh, and BTW the ratings for bulbs are not consistent. Thus you can't go by the kelvin ratings to get specific spectrums. Some of the lights show on the side the colors the bulbs give off. I believe the Power-glo has a lot of red spectrum and a little blue which help plants be more showy. Here more info on the spectrums

I was just thinking that I may have cause more confusion. My point is that the color spectrum is more important than the wattage. An example of this is Trallen44 tank here.
He only has 1 Zoo Med ocean sun 10,000K T8 32 watt 48" bulb

But at the moment i only dose my tank with Flourish:Comprehensive, and nothing else.
That is a good product. I accidentally bought it in a rush thinking it was Seachem excel. Plants have been doing good since I started using it. The gh of the water, type of plants and light will determine how many ferts you need to add. If you want to add more it may be cheaper in the long run to buy Plant Nutrient from Big Als. I would wait until you get the diy Co2 up. For I have seen some tanks that use no ferts with the diy Co2 and have great growth. Another good line of plant food is Bright well aquatics which was Kent at 1 time. You just got to weigh in the cost of getting the item.
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