Lighting needs for plants

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TigerBarbs

Aquarium Advice Addict
Joined
Jul 21, 2011
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On liveaquaria it says that almost all the plants need 2 watts per gallon of light! Is this true? Because i have a 29 gallon and its not easy to find a 48 watt bulb thats only 24" long.
 
No, watts per gallon is irrelavent. There is no 24" 48w bulb. You'd need a 2x24w T5HO for that. That's what I would recommend anyways... or a 1x24w T5HO if you can get one. I'd just run an actinic on a 2x fixture until you're ready to go high tech.
 
Not true ... I really don't like when websites give such blanket statements. High maintenance / light plants do need a high WPG .. but there are a few low light plants that do fine in less than 1.0 WPG.

Also ... from what I've read ... the WPG rule kind of goes out the window when dealing with higher output bulbs like T5HO bulbs. The link below I think provides a better way to detemine a tank's light level.

PAR vs Distance, T5, T12, PC - Updated Again Charts
 
Well... I have a senegal bichir which is a low light fish but want live plants so im kinda stuck right?
 
TigerBarbs said:
Well... I have a senegal bichir which is a low light fish but want live plants so im kinda stuck right?

Not at all, there are a ton of low light plants. Look on The Planted Tank Plant Guide or here is a list I found on APC

" This is an excellent list compiled James From Cali at: http://www.myfishtank.net/

"Plants Ideal For Low Light/Low Tech

Java Fern - Microsorum pteropus
Windelov Java Fern, Windelov Fern - Microsorum pteropus 'Windelov'
Narrow Leaf Java Fern - Microsorum pteropus v. 'narrow leaf'
Java Moss - Vesicularia dubyana
Green Hygro - Hygrophila polysperma
*Sunset Hygro - Hygrophila polysperma 'Rosanervig'
Ceylon Hygro - Hygrophila polysperma 'Ceylon'
Rotala Rotundifolia - Rotala rotundifolia
Rotala Rotundifolia sp. Green - Rotala rotundifolia sp. 'Green'
Rotala Indica - Rotala indica
Hornwort - Ceratophylum demersum
Parrots Feather - Myriophyllum aquaticum
Moneywort, Water Hyssop - Bocapa monnieri
Brazilian Pennywort, Pennywort - Hydrocotyle leucocephala
Crypt Wendtii - Cryptocoryne wendtii
Crypt Balansae - Cryptocoryne Balansae
Pygmy Crypt - Cryptocoryne pygmaea
Guppy Grass - Najas guadalupensis
Anubias barteri - Anubias barteri v. barteri
Anubias barteri 'marble' - Anubias barteri 'marble'
Anubias barteri v. 'glabra' - Anubias barteri v. 'glabra'
Anubias nana - Anubias barteri v. 'nana'
Coffee leaf anubias - Anubias barteri v. 'coffeefolia'
Crypt retrospiralis - Cryptocoryne retrospiralis
Crypt spiralis - Cryptocoryne spiralis
Golden nana - Anubias barteri v. 'nana golden'
Narrow leaf nana - Anubias barteri v. 'nana narrow leaf'
Petite nana - Anubias barteri v. nana 'petite'
Philippine Java Fern - Microsorum pteropus 'Philippine'
Red Java fern - Microsorum pteropus "red"
Crypt Becketii - Cryptcoryne becketii
Pelia - Monosolenium tenerum
Waterwheel Plant - Aldrovanda vesiculosa
Bacopa - Bacopa caroliniana
African Water Fern - Bolbitis heudelotii
Hornwort - Ceratophyllum submersum
Crypt Aponogetifolia - Cryptocoryne aponogetifolia
Micro Crypt - Cryptocoryne petchii
Tropica Sword - Echinodorus parviflorus 'Tropica'
Downoi - Pogostemon helferi

*Do not need high light to attain pink color. Dosing Iron can bring out this color.
__________________
 
It helps if your light is the right spectrum. Near 6500K is good. Actinic is NOT best for freshwater, that is for Salt Water tanks.

I grow a ton of plants under 5500-6700K

You can tie ferns or mosses to wood or rocks if you worry about the Bichir uprooting things. I just add basic liquid ferts 1x weekly after my PWC.
 
Lighting Question

Hello Tiger...

I'm into pretty simple "water keeping" and watts per gallon is a good starting point. If you keep low light, low tech (no CO2) tanks, you can grow low light plants with less than a watt of light per gallon of tank volume. In your tank, a 24 inch, 15 watt, 6500 K bulb will grow Java fern, Anubias, Pennywort, Cryptocoryne, Singapore moss and some of the less light demanding Amazon swords. If you get a little creative and float a small piece of driftwood, you can attach some Water sprite and Banana plants to it and they'll grow nicely.

Change out half the tank water every week and dose a good fert and you'll have a well planted tank in no time.

B
 
Whats the minimum lighting for anacharis?? Or what are other plants like it. Also would live plants help absorb poop throught the fine sand?
 
Growing Anacharis

Good morning Tiger...

Anacharis is a medium light plant. Most of the popular plants on the market will do well if you have between 1 and 2 watts of light per gallon of tank volume.

The fish waste that settles to bottom of the tank is one source of nutrients the plants need. That's why if you have a well planted tank, you don't want to vacuum the gravel.

B
 
WPG in reference to anything but plain-jane fluorescent lights is pretty pointless.

That being said- many plants do just fine with less than that old formula. Add to the mix, T5 and T5-HO which provide mire usable light per watt and things get tricky.

1 WPG of T5HO is considerably more usable light output per watt.

When I go serious about plants in my 29g, I picked up a twin bulb T5 HO fixture. With both bulbs on (using a timer), plants took off, but so did the Black Beard/Brush Algae and Staghorn algae. I had to get really aggressive with Flourish excel and then added DIY CO2 to deal with it. I cut back to one bulb and plants slowed down a bit (though still healthy growth), and the BBA/Staghorn issue also went away).

The more light, the more nutrients your plants will need- from the macros (NPK) to micro nutrients and CO2...
 
WPG in reference to anything but plain-jane fluorescent lights is pretty pointless.

I feel like we can keep saying that until we are blue in the face and people will keep asking if their wpg is enough to grow plants....
 
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This is my Anacharis in .55wpg in my 55g tank.

45770-albums2341-picture15560.jpg
 
55 G Planted Tank

Good morning xX...

Looks like you have a good start developing a planted tank. I have several 55 Gs with nothing more than a single 32 or 40 watt 6500 K bulb and can grow at least a dozen low to moderate light plants.

You can grow plants that require a little more light. They'll just grow more slowly in the lower light conditions.

If you dose a good hydroponics liquid fert, feed you fish a balanced diet and replace 50 percent of the tank water once a week, your plants and fish will have all they need to thrive.

B
 
Coursair said:
It helps if your light is the right spectrum. Near 6500K is good. Actinic is NOT best for freshwater, that is for Salt Water tanks.

The use of actinic bulb would be to bring out the colors of the fish more. What was suggested is to have 1 bulb at 6500k and then re actinic bulb so plants have enough light but the extra bulb isn't promoting algae growth.
 
WPG in reference to anything but plain-jane fluorescent lights is pretty pointless.

That being said- many plants do just fine with less than that old formula. Add to the mix, T5 and T5-HO which provide mire usable light per watt and things get tricky.

1 WPG of T5HO is considerably more usable light output per watt.

When I go serious about plants in my 29g, I picked up a twin bulb T5 HO fixture. With both bulbs on (using a timer), plants took off, but so did the Black Beard/Brush Algae and Staghorn algae. I had to get really aggressive with Flourish excel and then added DIY CO2 to deal with it. I cut back to one bulb and plants slowed down a bit (though still healthy growth), and the BBA/Staghorn issue also went away).

The more light, the more nutrients your plants will need- from the macros (NPK) to micro nutrients and CO2...

Good morning Batt...

The "Watts per Gallon" rule was helpful to me when I started in the hobby, only because is was easy to understand and the information was printed on the bulb. It was explained to me that the lighting meant the success or failure of my planted tank and to keep it simple.

That was six years ago, and my low tech, planted tanks are extremely successful. I'll take the "Watts per Gallon" rule and leave the lumens, VHO, HO, CRI ratings, etc. up to you smarter guys and gals.

Thanks for the comment.

Just one old "waterkeeper's" opinion.

B
 
The problem is that 2 wpg of PC or T5/T5HO is a surprising amount of light on tanks <20" deep. The wpg rules also become extremely hazy on smaller tanks, further deluding the issue.
 
Your Tank Lighting

Good morning Tiger...

Yes, there are some plants you can grow. Some of the less demanding, low light plants are Java fern, Anubias, most of the Cryptocoryne plants should grow. Pennywort and Hornwort should do well too. Don't forget that mosses prefer low light.

There are more than enough plants on this list to fill a 29 G tank. Attached are a couple of pics of two 30 G tanks I use to try different fertilizers and substrates. These two have a single 15 watt bulb each and the plants do fine.

B
 
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