Low lighting for emersed growth?
Planted Tank Forums
Your Tanks Image Hosting *Tank Tracker * Plant Profiles Fish Profiles Planted Tank Guide Photo Gallery Articles

Go Back   The Planted Tank Forum > Specific Aspects of a Planted Tank > Lighting


Reply
 
Thread Tools Display Modes
Old 07-21-2012, 03:04 PM   #1
nicks7.1985
Planted Tank Obsessed
 
nicks7.1985's Avatar
 
PTrader: (15/100%)
Join Date: Aug 2010
Location: Dundalk, MD
Posts: 413
Default

Low lighting for emersed growth?


Hi all ...the way i seem to understand it is..

if i have 2 identical setups one submersed one emersed both with say 20w light, the emersed will get a higher PAR as the light wont have to go through the water.

Does that mean that i can use the same light levels over an emersed setup as i would over a reg submersed setup and the plants should grow just a bit faster?


i realize i can blast pretty much all the light i can afford over emersed, but thats the problem lol...cant afford it haha. so im trying to figure out a minimum amount of light to use and still get regular (medium light) gowth for some hygro tiger that i have., then increase it from there..any suggestions?

thanks!,
Nick
nicks7.1985 is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 07-21-2012, 06:46 PM   #2
Hoppy
Planted Tank Guru
 
Hoppy's Avatar
 
PTrader: (74/100%)
Join Date: Dec 2005
Location: Sacramento, CA
Posts: 18,356
Default

You get more PAR with water in the tank than without water. The air to water interface slightly focuses the light, because off center rays are refracted a bit towards the center. And, with water in the tank the glass to air interface at the front, back and ends of the tank reflects a lot of light back into the tank, increasing the PAR near the glass.

Many of the aquatic plants we grow are found in partial to full shade in nature, so they are not adapted to grow in full sunlight - 1500-2000 micromols of PAR. I haven't found a good reference for the PAR in open shade or full shade, but it is probably around 500 micromols. So, if you want to use the maximum light that might be used by emersed plants, you could try for something around 200 to 500 micromols. That would be extremely high light for an aquarium.

You can get a lot of light, without spending a lot, by using 23-25 watt CFL screw-in bulbs in dome shaped reflectors less than 15 inches from the plants. I think that is what I would try if I wanted fast emersed growth.
__________________
Hoppy
Hoppy is offline   Reply With Quote Quick reply to this message
Old 07-21-2012, 10:59 PM   #3
nicks7.1985
Planted Tank Obsessed
 
nicks7.1985's Avatar
 
PTrader: (15/100%)
Join Date: Aug 2010
Location: Dundalk, MD
Posts: 413
Default

hoppy u r the man dude...maybe i should have pm'ed you on this lol ...you pretty much ans all my lighting questions anyway haha. thanks a lot for the info as always, it is appreciated!

one thing ...so if i used the same light 54w that is over my tank, the plants should still grow emersed..just slower?
nicks7.1985 is offline   Reply With Quote Quick reply to this message
Old 07-21-2012, 11:44 PM   #4
Hoppy
Planted Tank Guru
 
Hoppy's Avatar
 
PTrader: (74/100%)
Join Date: Dec 2005
Location: Sacramento, CA
Posts: 18,356
Default

I believe the plants will grow ok with the one bulb T5HO light. I doubt that many people try to overwhelm their dry start plants with a load of light. And, the dry start method has worked for a lot of people.
__________________
Hoppy
Hoppy is offline   Reply With Quote Quick reply to this message
Old 07-22-2012, 05:36 AM   #5
nicks7.1985
Planted Tank Obsessed
 
nicks7.1985's Avatar
 
PTrader: (15/100%)
Join Date: Aug 2010
Location: Dundalk, MD
Posts: 413
Default

i just set it up tonight and have 2x t5ho 54watt bulbs about 15 inches over the tubs. the lights are over a year old but still are quite bright...although i know it dosent mean they have the right wavelengths or w.e anymore,,,but we'll see what happens. ill put up some pics every week in the journal section.

i did set up 5 different tubs a bit differently and recorded them all with pics to see which works best..if it works at all.
nicks7.1985 is offline   Reply With Quote Quick reply to this message
Reply

Tags
emersed, light, par

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 09:02 AM.


Powered by vBulletin®
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright Planted Tank LLC 2012