Captive Aquatics: An Aquarium and Ecology Blog

What you Need to Know About Photosynthesis

 Photosynthesis is an incredibly complex process, but luckily for most aquarists only a basic understanding is required, but the time should be taken to understand that basic definition.  Photosynthesis is the “synthesizing by organisms of organic chemical compounds (Oxford Dictionary of Biochemistry and Molecular Biology [1997]), mainly carbohydrates, from carbon dioxide using energy obtained by light rather than the oxidation of chemical compounds”. Instead of consuming carbohydrates like we do for energy, photosynthesis can create carbohydrates for invertebrates and plants.  More simply, this means that plant cells can use energy gathered from light to produce cellular chemical energy (ATP) and carbon products (carbohydrates) when combined with carbon dioxide.  

Kelvin Temperature and Aquarium Lighting: What is Kelvin?

Beware, kelvin temperature is another mind bender!  Kelvin temperature (abbreviated as K), is the scientific unit for temperature, and is often used to measure the color temperature of light, or more accurately, the measurement of the temperature of an object emitting black body radiation, also known as thermal radiation, or radiant heat as visible light.  All objects at a temperature greater than absolute zero emit some form of thermal radiation, although at room temperature the wavelength of this radiation is too large for the human eye to perceive.  Still confused?

 

What You Should Know Before Purchasing an LED Light

The following musings began as a simple post on 3reef and ended up being quite long.  However, I think the info is valuable to anyone in the market for LED lighting.



There is much, much more that goes into an LED unit besides the diodes used. Top quality emitters can be used, but if you have supbar electronics, drivers, etc on the inside, then you have a subpar light. Sure, the diode might be rated to last 50k hours with a 30% output loss over that period, but what if the drivers used are only rated for 10k hours (plus, what are the specs of said driver: is it constant-current, constant voltage, what is the tolerance, variance range, etc?).

Looking to Purchase LED Lighting?

Looking to purchase LED lighting for your reef or nature aquarium  during the holidays?  Before you do, ensure that the manufacturer provides the spectrograph for the unit you are about to purchase.  PAR measurements are virtually useless for comparing LED lighting, one can only compare using PUR. 

T5 Spectrums: Choosing the Right Bulb for You

Since I use T5 lighting over my farm system, I'm always comparing different bulb colorations to use in different combinations. The spectral graphs of some of these bulbs are a pain to find sometimes, so here they all are in one place!

 

How to Choose and Compare LEDs - They're Not Metal Halides!

 
Whenever a new lighting technology comes along, hobbyists tend to attempt to compare it to a previous and more familiar technology.  This time around, LEDs are getting compared to metal halide lighting a lot, but it just doesn't work.



We all know we don't exactly use the scientific method in our hobby.  Terms such as watts per gallon, intensity, and brightness get thrown around all of the time, even though they mean absolutely nothing useful to us or our coral.  So, what's to be done?

The Aqua LED: Why Aren't Manufacturers More Transparent About Their LED Light Output?

Today I received an email from SolarMax that simply contained this flier (click for full size) about a product that is apparently new, and called "Aqua LED", and uses "Special developed SMD-LED chips". 

If my sarcasm isn't apparent, I'll say it straight: manufacturers need to give us more information than what's in this flier if they expect anyone to purchase their product, as most of us like to make informed decisions (from information written in gramnatically correct English, I might add). 

This issue of a lack of information applies to more than just SolarMax, and has created a false environment where only a few diodes are taken seriously by hobbyists - and this shouldn't be the case.

Aquarium Lighting and CRI - What is CRI?

CRI, or Color Rendering Index, is a somewhat dated term used to describe how accurately a given light will protray colors when compared to a reference light of the same color temperature.  While not typically used or measured for aquarium lights, this term has gained renewed interest due to the recent explosion in popularity of LED aquarium lighting.

PUR and Reef Aquarium Lighting: What is PUR?

PUR stands for Photosynthetically Useable Radiation.  PUR differs from PAR because the basic definition of PAR is any light in a specific frequency range.  PUR is the usable portion of PAR, and different photosynthetic species will have a different PUR range to which they respond. 

PAR and Reef Aquarium Lighting: What is PAR?

Photosynthetically Active Radiation, or PAR as it's commonly called, is a term that's widely used in the hobby, and is often not well understood, especially when applied to LED lighting.  When used correctly, PAR information can be very helpful in determining the best way to light a reef aquarium, and where best to place corals, clams, and other photosynthetic invertebrates.  When misunderstood, it can lead to unnecessary and costly lighting purchases and have detrimental affects on your reeef aquarium!