Saltwater Aquarium Blog

Reef Aquarium Lighting: Color Temperature Experiment Results

Reef Aquarium Lighting: Color Temperature Results 

This experiment in reef aquarium lighting was a visual, subjective exercise.  Rather than ramble on describing the differences between the combinations, I will let the pictures do the talking.  You can enlarge any of the pictures by clicking the thumbnail and viewing the full-sized image page.  The intent of this post is to report out on the color temperature experiment conducted using the new line of T5 high output (HO) lamps from ZooMed Laboratories.

Reef lighting is not only a critical life support system for your saltwater reef aquarium, it is also a major contributor to the overall look and feel of your tank.  In this experiment, four bulbs, with different color temperatures, were paired together in six combinations to assess the overall impact of the lighting combinations on the appearance of a reef display tank and the corals and fish who reside there.

Capnella species under combination 1

Capnella species under combination 2

Compare the results and subtle differences of reef aquarium light combination 1 vs. combination 2: CORAL SUN + ULTRA SUN T5 bulbs vs. FLORA SUN + OCEAN SUN T5 bulbs.

Note that the color on the left is relatively more brown, warm, and natural than the slight bluish/purple tinge of the combination on the right-hand side.

In these nearly identical pictures of a Colt coral (Capnella sp.), one can see the impact, although subtle, of color temperature on the appearance of the tank and its inhabitants. 

Both combinations are noticeably bright–not surprisingly because the ULTRA SUN and OCEAN SUN lamps were in opposite pairs.  I would characterize the overall color temperature of pairs 1 and 2 to be mostly white.  There is only a subtle detectable difference attributed to the brown/red glow from the FLORA SUN (left)vs. the blue glow of the CORAL SUN (right).

Devil's Hand coral species-combination 4

Devil’s hand coral combination 3

 

 

 

Compare the results and subtle differences of reef aquarium lighting combination 3 vs. combination 4: CORAL SUN + OCEAN SUN T5 bulbs vs. FLORA SUN + ULTRA SUN T5 bulbs.

 

Note the cooler blue and yellow tones of the coral picture on the left, and the warmer orange/brown tones of the coral on the right.  Combination three provided an appealing ‘glowing’ look, whereas combination four provided a more natural ‘true-color’ look and feel.  While these pictures focus primarily on an individual coral specimen, the image posted here is reflective of the effect which the bulbs had on the entire tank.

 

 

Clownfish and colt coral under combination 5 lighting

 

Clownfish and colt coral under combination 6

Finally, consider the last pair of images–

Compare the results and subtle differences of reef aquarium lighting combination 3 vs. combination 4: CORAL SUN +OCEAN SUN T5 bulbs vs. FLORA SUN + ULTRA SUN T5 bulbs. 

In this comparison, the puple and pink colors really pop on the left-hand side, in the clownfish as well as in the colt coral–and the purple colors of the coralline algae on the live rock amost glows. The lighting on the right-hand side has a bright white appearance–making the colt coral appear tan, the white tile next to it looks white and the clownfish actually have a natual looking color.

As you can see from the images–seemingly minor changes in light bulb color temperature can have an impact on the appearance of your tank.  To keep the arms of the experiment to manageable set, I only rotated the lamps in combinations of one bulb for each temperature–but the impact of a particular bulb style on the appearance can be further amplified or fine tuned with a variation of the number of bulbs from a given color temperature range.  A finer level of precision could be achieved to create the optimal color combination for your individual reef needs. 

 

More conclusions, takeaways and advice to come in the next post.

Reef Aquarium Lighting: Color Temperature Experiment Continued

Note color temperature range: warm to cool

Note in the picture that the appearance of the light output ranges from the red/violet  hue of the FLORA SUN (far left) to the deep blue actinic of the CORAL SUN lamp(far right).  In the middle, it is apparent that not all ‘white’ bulbs are the same.  Take a look at the difference between the stark white ULTRA SUN lamp (left middle) compared with the bluish/white OCEAN SUN lamp (right middle). 

The light fixture over the display tank is four foot long and runs 4×46 inch T-5 High Output (HO) lamps.  The lamps are wired in pairs with each pair connected to an independent switch.   

The four lamps, connected in pairs, created six possible combinations.

Pair combinations for the Reef Aquarium Lighting Experiment

The lamp combinations were toggled back and forth leveraging the two independent switches in the following fashion:  

Note: First and third T-5 lamp are wired together

Note: Second and fourth lamps are wired together

The lamps in the first and third positions were wired together as teh first combination and the lamps in the second and fourth positions were wired together as the second combination.  Appearance of the tank was judged qualitatively according to relative warmth of the light and a general color and appearance description. Photographs were taken of the reef tank with the various color combinations to capture the possible differences

 More pictures and results to come….

Reef Aquarium Lighting: An Experiment in Color Temperature

Reef Aquarium Lighting–An Introduction to the Experiment

Reef aquarium lights come in a range of color temperature--shown here are the four available color temperatures available from ZooMed Laboratories

Over the next several blog posts, I’m going to explore the topic of reef aquarium lighting.  For many reef aquarium hobbyists, lighting will be one of the most expensive pieces of equipment in their system.  Lighting is expensive to purchase and to run on a daily basis.  For photosynthetic invertebrates in your tank however, reef aquarium lighting is also one of the most important pieces of equipment because the light provides the life sustaining energy to the tank.

The topic of reef aquarium lighting is often explained from a complex, technical point of view.  Most saltwater aquarium lighting articles read more like textbooks than articles.  And quite frankly speaking, lighting is a complex topic.  However, one aspect of reef aquarium lighting that often gets overlooked is the impact that lighting has on the aesthetic appearance of your tank.

From a technical perspective, the ‘look and feel’ produced by a light bulb is a function of color temperature.  Over the next few posts, I will reveal the effects of lamp color temperature on the appearance of the display tank in my den, and more specifically the effects on the appearance of the vertebrates, invertebrates and algae living in my tank.

The four reef aquarium lights (lamps) used in this experiment are:

• 10,000K Ocean Sun®
• 6,500K Ultra Sun®
• 5,000K Flora Sun®
• Actinic 420 Coral Sun®

A special thank you to a loyal sponsor of this site, ZooMed Laboratories, for providing the high output T5 fluorescent lamps used in this experiment.

Tropical Fish Hobbyist Magazine Online For $1: Now Available on iPad

Tropical Fish Hobbyist (TFH) Magazine is running a promotion from June 23rd to July 23rd where you can subscribe to a year of the magazine’s online version for just $1.  Not a dollar an issue–one dollar for the entire year.  Here is what the online version of the magazine looks like on the iPad:

 It doesn’t look like TFH created a specific app for iPad–but clearly the iPad provides a great user experience to read the magazine.

And if getting a $28 (paper) subscription for a dollar online wasn’t a good enough deal for you already, their website states that new subscribers to the digital version will also be entered in drawing to win an iPad.  So take a look at the offer and see if it’s right for you.

Check it out for yourself and sign up:
 http://www.tfhmagazine.com/ipad/

Breeding Banggai Cardinalfish Article

Be sure to pick up the August edition of Aquarium Fish International, and check it out. I have two articles

Cardinalfish mouth full of eggs

published in the August edition of the magazine–a full length article about breeding the Banggai Cardinalfish titled “Six Steps to Breeding the Banggai Cardinalfish”  and a hobbyist tip on establishing a ”Low Cost Tank” the last page, in the Aquarist’s Notebook section.  

Banggai Cardinalfish Fry Just Released from Father's Mouth

In the article, I relay my experience with breeding these spectacular fish (the Banggai Cardinalfish) while on vacation.  While it was a bit of dumb luck at the time, it turned out that the protocol I used to get my tank ready for vacation created a few time tested spawning triggers.  My account of this accidental breeding is intended to be reassuring to the casual hobbyist and a testament to the resiliency of these fish once properly acclimated to captivity (or already born in captivity).  You’ll see the mistakes I made along the way, and I provide as much advice as I can cram into an article. 

Rotifer Culturing at Home: Continous Cultures

Rotifer Culturing at Home: Continuous Culture Set-Up and Protocol

Growing rotifers as a continuous culture is easy to do, but requires a small amount of work, almost every day. Unlike batch culturing, where the goal is to culture the most rotifers possible in sequential batches, the goal of continuous rotifer culturing is to create a long-lasting, stable, low-density culture.  To create a continuous culture at home, follow the protocol below:

Materials:

• Several feet of flexible airline tubing
• 2 twelve inch lengths of rigid airline tubing
• 2 buckets (old salt buckets—or other, as long as they are clean and chemical free)
• Saltwater~1.014 specific gravity
• Live phytoplankton culture (for use as rotifer food)
• Rotifer starter culture harvested from your batch culture

Protocol:

• Take approximately 1.5 liters from your ready-to-harvest rotifer batch culture, as listed in the previous protocol.  Add the volume to your first culture bucket.
• Add two liters of salt water to increase the culture volume
• Add enough phytoplankton to the culture to turn the culture to a light green color
• Attach the flexible airline tubing to the rigid airline tubing at one end and to the air pump on the other end and insert the tubing into the bucket to, create a moderate flow of bubbles.
• For each day over the next week, add approximately 2 more liters of saltwater and enough phytoplankton to  tint the water a light green
• When you have about four gallons of culture, pour half of the volume into the second culture bucket, add about 2 gallons of saltwater to each of the two buckets and insert the airline tubing to create a moderate flow of bubbles
• Add enough phytoplankton to tint the cultures each light green
• Final step: Every day, harvest about 2L to 1 Gallon of culture, replace the volume with new saltwater and tint the water light green with fresh phytoplankton

Saltwater Aquarium Blog Tip:
The key is to add just enough phytoplankton so that the culture turns a light green color—and that the rotifers are able to clear the phytoplankton every day.  If you add too much, there is a risk that the density gets so high that the culture will crash.  So add modestly and consistently

Advanced Aquarists Tip:
As you get more confidence with your culturing technique, you can control the density by varying the amount of phytoplankton that you feed them.  If your fish have just spawned or you need more rotifers for whatever reason, you can get a ‘burst’ of rotifers by spiking the culture with more phytoplankton.  Be warned however that the higher density the greater the risk of the culture crashing—so if you spike, make sure you harvest aggressively and keep replacing the water volume

How to Culture Rotifers: Batch Culturing Protocol

Culturing rotifers at home is fairly easy to do.  Rotifers are a great food source for newly hatched fish larvae and for some filter feeding invertebrates.  Ironically, the rotifers organism itself provides very little nutritional value to the animals that eat them. 
It is the content of their guts (the food they eat) that provides the nutrition.  As such, it is important to feed your rotifers with a highly nutritional food source, like phytoplankton.  If you’re serious about culturing rotifers at home, consider also culturing phytoplankton.  While it’s important to keep the cultures separate and avoid contamination, the skills needed to culture phytoplankton and rotifers are similar. For more information about phytoplankton culture, check out the phytoplankton page.

There are two popular ways to culture rotifers: as a continuous culture, or as a batch culture.  The following blog post will present the protocol I follow to batch culture rotifers at home.

Rotifer Batch Culture Set-Up and Protocol

• Cut 3 lengths of 12-inch rigid tubing and 4 lengths of flexible tubing: 3 long enough to reach from the bottles to the splitter and the fourth long enough to run from the air pump to the splitter
• Attach flexible tubing to splitter, pump and rigid tubing. Insert rigid tubing into culture bottle
• Turn on air pump
• Fill bottles with a small amount of freshwater to test and make sure all 3 airlines create a modest flow of bubbles. Adjust flow rate on the splitter as necessary to create uniform moderate flow.
• Empty the bottles and inoculate the first bottle with a starter rotifer culture
• Add a few ounces of phytoplankton, make sure aeration is on, and watch the culture over each of the next few days.
• When the water ‘clears’ to a light green tea-colored tint, and you can see little specs in the water when you hold the bottle up to a bright light, add a few ounces more phytoplankton.  Over a few days, by adding more  phytoplankton when the culture clears, increase the total culture volume to about ¾ of the bottle (about 1.5L
• After another 1-2 more days, once the1.5 liters of rotifers have cleared the phytoplankton, it’s time to start your second culture. Take approximately 1/3 of the culture (approximately 0.5L) of the tea-colored liquid and pour it into a second plastic bottle.  Fill each of the bottles to the top with phytoplankton.  In this way, the original bottle will be ready to harvest about a day before the second bottle.  Repeat this step to create as many culture bottles as you want. By varying the mixture of phytoplankton volume and rotifer culture volume (or density) you can optimize your cultures to be ready for harvest when you will need it.
• To harvest the rotifers, pour out about ¾ of the tea colored culture through a rotifer sieve (approximately 50-55 micron) and into a discard/water change bucket
• After you have ‘filtered’ ¾ of the culture through the rotifer sieve, turn the sieve upside down over second bucket (or small office-sized trash can dedicated to fish-room use), scoop up a cupful of the discarded culture water and pour it slowly over the upside-down rotifer sieve, effectively reversing the flow of water and rinsing the collected rotifers into your collection bucket/trash can. Collect the concentrated rotifers, feed them to your tank or store them in the refrigerator for later
• Fill the rest of the bottle (the remaining 1.5 liters), with fresh phytoplankton and start bubbling again

• Saltwater Aquarium Blog Tip: Instead of rinsing the rotifers from the rotifer sieve with discarded culture water, you can replace it with water from your display tank or with freshly made saltwater.  That way you can add rotifers to your display tank without adding, the impurities of the culture water. 
   
• Advanced Aquarist Tip: The key to surviving culture crashes—which you will have—is redundancy.  You always want to have multiple cultures working at the same time.  If you do, chances are good that at least a few rotifers from one of the cultures will survive. Just place the crashed culture(s) aside, get some new plastic bottles and use the survivors to seed a new batch.

Earth Day 2010

Earth Day 2010

This year marks the 40^th anniversary of Earth Day, a day set aside to observe, recognize and respect the importance of the natural world.  Those of us who enjoy the saltwater aquarium hobby, by our very nature, may already be inclined to respect the ocean and her bounty, but there is still an opportunity for each of us to be mindful, this Earth Day 2010, of the impact our hobby has on wild reef habitats. This Earth Day, let’s take a moment to consider what it means to be a responsible reef-keeper, and remind ourselves of the admirable goals of minimizizing the negative impact we have on wild reefs and help educate others about the importance of our reefs and the inhabitants of our tanks.  Let’s also agree, as hobbyists to keep the following principles in mind:

Avoid purchasing notoriously difficult to rear species, like the Moorish Idol.  Also avoid purchasing endangered or threatened species, like the (wild-caught) Banggai Cardinalfish.  These fish may be stunning to behold, and in high demand, but they are also notoriously difficult to maintain in captive aquaria.  So this Earth Day, let’s remember why it is so important to avoid supporting the collection of endangered or difficult to raise species. 

Let’s also take a moment to appreciate the contributions that aquaculture has made in alleviating some of the pressure of collection on wild reefs.  Aquacultured specimens, both invertebrate and vertebrate, are generally more tolerant of the conditions in our reef tanks and typically acclimate better.  There are clear advantages to purchasing aquacultured specimens, so let’s make a pledge this Earth Day to buy aquacultured coral and fish whenever possible–even if it costs a few dollars more.

Finally, consider donating this year to a non-profit organization that supports the conservation of or rebuilding of the world’s reefs.  For example, record cold temperatures in Florida this winter are thought to have caused major damage to reefs—damage that will take years to recover from.  Non-profit organizations like www.coralrestoration.org use donations to fund the growth and replacement of reef-building stony coral species to help them retain a footprint on the reefs, recover and re-grow.    

Take an extra moment this Earth Day to appreciate your reef tank and the inhabitants of our slice of the reef that captivate our attention and entertain our guests.   

Check out the new T5 HO lights available from ZooMed, these lights provide light output than T8s!

Be sure to register on the site and post your plans for demonstrating your commitment to responsible reefkeeping.

Rotifer Batch Cultures

Rotifer Batch Cultures

Culturing rotifers with a batch culture technique is akin to a manufacturing process.  Instead of focusing on creating a stable environment to keep a relatively low-density culture thriving over a long period of time, the objective of a batch-produced culture is to maximize the yield of the culture over a short period of time.  With a batch culture, you start the culture at a low density and feed them enough to allow them to proliferate to their maximum density.  The density achieved is greater than in a continuous culture because the it is maintained only for a short period of time before the cutlure is restarted.  The trick is to harvest the rotifers at their peak density and restart the batch.  In this fashion, the rotifers are continuously reproduced, but at a much higher density.  As such, you can maintain a lower culture volume yet produce a higher number of rotifers.

I culture rotifers in a 2L juice bottle, but you can use any size that suits your space and culture needs.  The batch culturing process is fairly straightforward. Begin with a small starter culture. I fill the rest of the bottle with Nannochloropsis phytoplankton.  I insert the airline tube and watch.  Over the next few days (3-4) the culture water will transform from a dark, robust green to light green, to yellow/light brown. If left alone for another day, the water will clear, except for the rotifers, which will appear to be tiny ‘specs’ visible with the naked eye. 

For maximum nutritional value, harvest the rotifers while the culture is still tinted light green.  The rotifers themselves carry very little nutrition.  However, the phytoplankton inside their digestive tracts is highly nutritious. So the rotifers will provide the most nutrition for your reef tank or fish larvae when their guts are packed with nutrients.

Advantages of Batch Rotifer Cultures

• Rotifers are produced at the highest densities possible. 
• Since the majority of the culture volume is turned over every few days, crashes are less of a risk
• Maintenance is only required a few times per week, depending on how many cultures you are running and what the timing between harvest of each culture

Disadvantages of Batch Rotifer Cultures

• The culture must be harvested within a day or two of reaching the top density, if not, the culture will run out of food, oxygen and crash
• You will definitely need multiple (redundant) cultures unless you plan to harvest just one day a week

Rotifer Cultures: Continuous Rotifer Culture and Production

Rotifer Cultures: Continuous Rotifer Culture and Production

There are two popular methods of culturing rotifers—continuous culturing and batch culturing.  Each method has its own pros and cons, but the next two posts should help you decide which method is right for you.  The focus of this article is to describe the process of continuously culturing rotifers and identify some of the advantages and disadvantages of this method.

Rotifer Continuous Cultures

Culturing rotifers with a continuous process is analogous to the way we maintain our reef tanks. With a continuous system, your goal is to create a stable habitat for the rotifers to thrive in.  Like the inhabitants of your display tank the rotifers need clean saltwater, food, oxygen and light.  Provide them with a suitable environment, and the rotifers take care of the rest.  However, unlike the fish and coral in your reef tank, a healthy rotifer population will double almost every day.  Left unchecked, twice as much food and oxygen would be needed, and twice as much waste would be produced, every day, spiraling out of control until the culture eventually crashed.  In order to keep the culture from crashing, you need to perform maintenance, almost daily.  You will need to harvest enough rotifers to keep the population stable, perform regular partial water changes and feed them.

Since the focus of this methodology is on maintaining a stable, reproductive population, you can transfer some of the knowledge you gained in creating a stable reef aquarium.  For example, with increased volume comes increased opportunity for stability—larger culture volumes, in general, will be more stable than smaller culture volumes.  The larger volume of water creates a greater margin for error, thus giving you a little slack.  The key is to estimate your demand—how many rotifers will you need? How large of a culture can you reasonably maintain? How much space are you looking to devote? And establish a culture that suits your individual needs. 

As with any decision in life, the decision to culture rotifers continuously instead of as a series of batch cultures has advantages and disadvantages, that you should consider.

    Advantages of Continuous Rotifer Cultures

• Rotifers are available for harvest and use every day
• Small equipment footprint—all your equipment can potentially fit in a compact area since you will primarily be culturing in only one or two vessels
• Relatively larger volumes of cultures have the potential to be more stable and be insulated against small swings in water parameters
• You will eventually develop a fast, streamlined process to perform the maintenance duties, since you will have to keep up with maintenance every day

Disadvantages of Continuous Rotifer Cultures

• Continuous cultures run at lower densities than batch cultures—as a result, you produce fewer rotifers per Liter of culture media
• Crashing—continuous cultures may crash from time to time—if you don’t have a back-up (redundant) culture running you may have to start over from scratch
• Continuous rotifer cultures require continuous maintenance. The work-load is spread out, since you will perform a little bit of work every day, but you may have culture crashes if you miss too many days in a row.

Further Reading:

For more information about culturing Rotifers, check out these books: