February 2009 Meeting

Monday, March 2nd, 2009 at 9:11 pm

GWAPA’s February 2009 meeting was yet another great event, with over 30 people in attendance, and 99 items in our “mini” auction! Rick and Mary Dotson graciously hosted this month’s meeting, and Rick engaged everyone in attendance with his talk on Aquarium Lighting.

February 2009: Rick & Mary's 75G

First, some announcements–

  • The annual Nano Competition is gearing up. After much deliberation the contest will remain as 2.5 gallon tank size, but may be expanded next year to include (or completely change over to) bigger 5.5 gallon tanks. Registration will begin in the next few days, and there will be a link with more information and pricing on the forum.
  • Aquafest 2009 planning is underway! Our tentative speaker this year will be Jeff or Mike Senske, extremely talented and proven aquascapers, and co-owners of ADG, the world renown ADA’s U.S. distributor. Since GWAPA is helping to organize and run the event we will also be needing volunteers to help out throughout the weekend. When we get closer to the date more specifics will be available on these opportunities.

February 2009: Rick's Lighting Presentation

On to the hot topic…Lights!

Rick was ready for business with a very informative PowerPoint presentation (click here to download the presentation) to aid in the discussion, and opened the floor to Sean Murphy and Jim Michaels to share their knowledge as well. He talked about the variables in lighting that are key, how long the lights are on, and how much light actually gets into the tank. Photosynthesis only occurs in plants for 10-12 hours per day, therefore, any light shed after that time period simply isn’t used by the plants, but will still be used by algae which can contribute to algal bloom. That said, timers are essential to regulate the amount of time your lights are on each day. The amount of light that gets into your tank is measured in lumens, which is the power of light. You can measure this with a Lux meter which will measure light in lumens per square meter. A common misrepresentation of light strength is measuring your lighting in watts, as that only defines the amount of energy the light unit uses (this is more clearly illustrated on a chart in the PowerPoint presentation).

February 2009: Room full of people!

Factors that can reduce the amount of light getting into your tank are cheap reflectors (like the ones that come in the “petstore special” deals with tanks), dirty bulbs, floating or untrimmed plants, and the actual depth of your tank. This last point is important to note, up to 24″ deep there is no real difference in light penetration, but after 24″ the amount of light that reaches the bottom decreases exponentially. In these tanks you can essentially throw out the watts-per-gallon (WPG) adage. An example given was this: Jim has a 110 gallon x-high tank lit with 3.9 WPG metal halides. Ghazanfar has a 215 gallon tank lit with 3.5 WPG, also metal halides. While Jim’s tank has a higher WPG rating, when measured and calculated with the depth of the tanks being lit Jim’s tank has 14.8 watts per inch vs. Ghaz’s 25.9 watts per inch. This explains why Jim had difficulties growing foreground plants at the substrate level where Ghaz had lush growth.

The color of your light spectrum is also very important. While the human eye can barely tell the difference between the spectrums, plants are quite sensitive to the different arrays. Actinc bulbs are bad for growing plants, while popular in 50/50 bulbs they are intended for use in marine or reef tanks where their more blue spectrum is like the light that reaches deep into the ocean for corals. Generally light spectrums more towards the red end will give more tall and leggy growth, whereas more blue light will lead towards compact and bushy growth. The best spectrum for growing plants is from 5500-6500k, but up to 10,000k is ok (and some aquarists prefer the look).

The best kind of light to get is fairly subjective. Of the options readily available, the Compact Fluorescent (CF), T5, and Metal Halide (MH) are the best choices. Of these, the MH has the highest initial buy-in price, but best performance and cheaper maintenance costs. The T5 and CF are fairly comparable in price when you factor in both the buy-in and maintenance costs. Light types to avoid include VHO (Very High Output) fluorescent lights, as they are expensive, old technology, run very hot, and are not terribly efficient and mercury vapor lights as their light spectrum is nowhere near what is needed by your aquatic plants. A relatively new trend in the hobby is LED lighting, as Sean Murphy then demonstrated, but to date it is still very expensive and generally out of the price range for most people. Although after the initial purchase there is minimal energy usage (compared to the other lighting options) and lifespan for the bulbs and unit is incredibly long (ten+ years). Another benefit of LED lighting is that the lights are directional, and don’t rely on reflectors to aim the light in a desired direction. Before you go running out to your local Pep Boys to pick up some LEDs to hook up remember that as with any light, the spectrum is key. The LED bulbs must be at specific nanometers to properly grow plants, and these nanometers are difficult and expensive to reproduce in LED materials. Unless you can determine exactly which bulb you get chances are it won’t be what you’re looking for to use on your tank.

There are numerous ways to make your cheap light strip better…from upgrading the type of bulbs with a retrofit kit to updating your reflector. One easy remedy is outlined here by one of our members Aaron Talbot. It’s a way to overdrive a standard shop light you can find at your local hardware store.

In general, plants can tolerate more intense light than you may think, but not in extremely long durations. There is plenty of debate about the duration of lighting, with the general consensus being anywhere from 10-12 hours. Sean interjected another tidbit of sense, in nature the first few hours and last few hours of sunlight is mostly reflected off of the surface of the water due to the angle at which the light approaches the surface. He recommends that 8-10 hours of light more closely mimics natural conditions. Also, Sean surmised from his experience, you will find less algae in higher-intensity, lower duration tanks than in lower-intensity, longer duration tanks.

All in all there are lots of choices out there for aquarium lighting… some good, some bad. But if you do your research and take advantage of the wealth of knowledge others have gained you can save time, energy and money making mistakes and find yourself with a beautiful planted tank full of flourishing life!

Pictures from the meeting

Thanks to Jim Michaels and Kris Weinhold for the meeting photos!

February 2009: Rick & Mary's 75G, angle

Rick & Mary's 75G

February 2009: Mary's ADA Tank

Mary's ADA Tank

February 2009: Rack of Tanks

Rack of Tanks

February 2009: Room full of people!

Room full of people!

February 2009: Listen to Kris' announcements

Listening to Kris' announcements

February 2009: Rick's Lighting Presentation

Rick's Lighting Presentation

February 2009: Dave Auctioning

Dave Auctioning

February 2009: Darlingtonia californica

Darlingtonia californica

February 2009: Cephalotus follicularis

Cephalotus follicularis

February 2009: Pygmy Sundews

Pygmy Sundews

February 2009: Venus Fly Trap

Venus Fly Trap