Badman's Tropical Fish

All-Water Boards => Aquatic Plants and Algae => Topic started by: Gregg on February 20, 2016, 10:35:53 AM

Title: Better lights for a stock hood.
Post by: Gregg on February 20, 2016, 10:35:53 AM
I am trying to use as little plastic as possible in two tanks I have. Both share the same size hood and lighting, they fit a 15 long and 20 high.  Both have course gravel substrate so I use rhizome plants, and some floating, one has a nice matt of Monosolenium tenerum, the shallower 15.  My list is, java fern, Anubias nana, and also unknown anubias, floating pennywort, (it remains sort of status quo,) some water wisteria, also barely hanging in there, some java moss, (it just simply lives status quo also,) and guppy grass, Najas g.  The plants do best in the 15 long by far. It has some sunlight as well. This is the 15 long.<a href="" target="_blank"><img src="" border="0" alt=" photo 004_zpsudmdr0kh.jpg"/>[/url]
My 20 high,<a href="" target="_blank"><img src="" border="0" alt=" photo 001_zpsic29xofb.jpg"/>[/url]
OK, I have a 15 watt Aqueon full spectrum light (it seems like a conspiracy as there is at least 4 inches of wasted space in the light fixture,) and can't help but wonder if a plant type t8 bulb may be better, or not.  I understand this light has less than 5000k.  I weekly with a water change use the recommended dose of Seachem Flourish.  I am not willing to mix dry ferts or spend much more on micro or macro ferts.  I'm hoping that there is a bulb that will help me with what I have.  The lights are on 10-11 hours a day


Title: Re: Better lights for a stock hood.
Post by: gunnered72 on February 21, 2016, 12:43:12 AM
Your lighting tubes should be changed every nine months in my opinion....They loose their efficacy over time and plants suffer as a result...

Your lights are on too long in my opinion (8 hours max is my recommendation)

The Flourish dose should be split up through the week (3 times a week IMO) Forget what it says on the bottle as regards weekly!

You should also daily dose Excel (Liquid Co2)

Follow these instructions and watch your plants improve and your algae growth deminish......

Title: Re: Better lights for a stock hood.
Post by: Gregg on February 21, 2016, 10:47:12 AM
Thanks for your reply!

I changed the 20 gallon tank's light recently.  The 15 needs it done.  I have heard about using less light.  In a natural day it is longer.  I then take it that the enclosed system we use is the reason?  I did my water change in my 15 yesterday and I was surprised by how well things were doing.  It looks like I may have to find a home for the guppy grass, it is doing very well.  The only plant that really is struggling is the water wisteria.  In the 20 high I get algae on the anubias leaves but the floating pennywort and especially the water wisteria, which refuses to die, is struggling.  So from this I take it that perhaps my light spectrun/intensity=however you measure it, par value, lumens, K rating, is not correct?  Or, maybe I should stick with what the single bulb I have will grow?  Speaking of that I purchased a new 10 gallon tank for my Q tank, and the hood has an 18" t8 bulb as does my 15 and 20. What gives!  I may be hoping for a bulb aid that does not exist. I have used, by the way, Excel, in both tanks and it began, I am sure, to destroy my Monosolenium.  I also found it made my guppy grass spindly.  I under dosed I will say. 


Title: Re: Better lights for a stock hood.
Post by: russ on February 21, 2016, 12:40:52 PM
This may help you understand lumens and K rating, etc.

To answer your question about K and in anticipation of a few more you may have, here are some lighting terms and basice definitions:
K (kelvin):  represents color temperature. This indicates the color appearance of a light source.
CRI:  color rendering index, indicates the color appearance of the objects lit by that source.  

Lumen:  is a unit of measurement of light. It is a way of measuring how much light gets to what you want to light. A foot-candle is how bright the light is one foot away from the source. A lumen is equal to one foot-candle falling on one square foot of area.  

Watts: is simply the amount of energy consumed by the lamp. It has nothing to do with the amount of light produced by a lamp.

5600K represents noon day Summer sun. 6500-7500K would represent an overcast sky. A kelvin rating between 5500-6500K will fit most hobbyist's freshwater planted tanks happy Full spectrum light source tubes would be between 5000 and 7000 K.

Plants take in and use light in both the red and blue end of the spectrum. They also use it in the green, yellow, and orange. We just happen to see colors better in that spectrum also.  :happy:

My wife had scavenged this in an older reply from one of my previous replies regarding DYI modifications to a standard tank kit light hood/refleftor:

"Here is another for the DIY minded...................

If you go the stickily economic path and replace or keep  your hood with a standard, so-so florescent lamp, there are inexpensive DYI ways to jazz it up and make it more efficient.

Standard lamp hoods do not do a very good job in handling light other than to provide a decorative anchor from which the light operates. There are several ways to adjust this. First you need to account for{'light spillage'.}

Only 75% or less of the total light output actually shines on the area you want it to go. 25% or more of the light is basically going to waste. Controlling this {spillage} goes a long way to utilizing your current lamp in a more effective manner.

A step in the right DYI direction would be to identify that which is causing that 25% loss. This is most likely caused by poor light insulation. In other words keeping the amount of light you have available in order to have it directed where you want it. (in your aquarium).

To enable you to direct this light, you need an efficient reflector. By combining a more effective way of trapping your available light with a good reflector, you can direct up to 95% or more of the light output where you want it.

Modifying your light hood/strip, in your case, would be a way to accomplish most of this. Remember, even with a brand new standard light hood and lamp, only 75% or less of the light output is going into your tank. Since these hoods do not utilize a parabolic reflector, you'll have to make do with placing a higher reflective material inside your hood than that which came with it.

If you have a glass canopy and plain light strip, start by painting the outside top of this canopy black. Paint the underside of the canopy white. Needless to say, you must account for the area of the canopy that will not be painted in order to accommodate the strip hood and area that the light will shine through to the inside of your tank. If you obtain a full hood (the plastic type), paint the underside of the plastic parts white. Just by doing this, you will be able to increase that original 75% by at least another 5-10%.

Next would be the inside of the light strip. There several excellent materials available through your local paint and hardware store. Mylar is a good material with a 95% reflective ratio. It is a bit brittle and can tear easily, so care must be taken if using this. Aluma-glo is like Mylar, but is meshed to form a sturdier application. This reflects with about a 94% efficiency. The best material to use in a DYI reflector is Foylon. This is similar to Aluma-glo but has a 97& efficiency.
This will take care of redirecting the light that is projecting downward from the lamp, while the white under-surface of the canopy or full hood will redirect the light traveling upward."

Title: Re: Better lights for a stock hood.
Post by: Gregg on February 22, 2016, 09:45:49 AM
Good stuff russ!

That was another  block of information I can keep forever.  My under standing of the Kelvin scale for fresh water was way off. I use mylar in a micro means tying flies, so I know it's reflectivity.  I must ask if aluminum foil, which I have right away, is an option?  I'll look this up as well as the options you mentioned.  I do realize that my two floating choices desire higher light levels it seems.


Title: Re: Better lights for a stock hood.
Post by: russ on February 22, 2016, 08:39:36 PM
Ordinary aluminum foil will oxidize under the heat build up in the hood. In-turn, it will actually greatly lose it's reflective ability. I suppose you can keep changing it each month or less if that is more economical than the other materials. With that in mind, yes, it would be an option.