A Complete Idiot's guide to understand LED

For more such tutorials and fishy pictures, visit my website: www.playsofrays.com

LEDs are the new ‘IN’ in the lighting world and so is in our hobby where lighting is an essentially important. Be it reef, planted tanks or simple fish setups, light is needed everywhere.
We have been using CFLs, PLLs, metal halides, T5s, T8s, T12s etc for our lighting needs but after LEDs have hit the market, they seem to be the best lighting solution. Let’s have a look at some of their pros and cons -
 
PROS-
•    Very low electricity consumption.
•    Very high light output.
•    Long lasting components.
•    Economical in the long run.
•    Very small in size.
•    Latest in technology.
•    The wavelength of the LED can be customized according the need by the manufacturer.
 
CONS-
•    High initial cost.
•    The cost of other components needed to make a LED light unit.
•    The heat produced.
•    Very fragile. Care must be taken when installing.
And as we all know, hobbyists need a single reason to start something new ;) And we have so many.

PAR

Before starting the discussion on LEDs I’d like to explain one thing. PAR - which stands for Photosynthetically Active Radiation.

We have been measuring the lights in our tanks in Watts per gallon.
Let’s just assume there are two tanks of same capacity, say 10 Gallons, but their heights are different. One is 14” in height and the other one is 9” in height. If we put the same light at the same height over both the tanks, would light reaching the bottom of the tanks be the same ??
NO… It would never be the same. So, its time we stop using WPG in our fish-talks.
Let’s discuss PAR in a little more detail now.
Light intensity can be measured in lux, which is the intensity as perceived by human eyes. Or, it can be measured in PAR units, which is the intensity as perceived by plants. PAR stands for “photosynthetically active radiation” - the radiation (light) that is used by plants for photosynthesis. The units of PAR are micromoles of photons per square meter per second. So, a PAR of 1 is one millionth of a mole of photons striking a one square meter area every second.

Don’t worry it’s not that complicated. Our eyes see the yellow and green part of the light spectrum  which means our eyes are sensitive to yellows and greens. Plants are very sensitive to reds and blues, so they absorb most of the light in reds and blues, but less sensitive to yellows and greens, reflecting a lot of the light in these colors. That is why most plants look green or yellow. [We see colors because the thing we see has absorbed all the colors in the spectrum except the color we see].

How to measure the PAR! There are meters available in the market just like meters available to measure voltage, current or pH. Nowadays the light manufacturing companies are promoting their products by advertising the PAR values of their lighting products.

PAR value of any light decreases gradually as the distance from the light source increases. That means the nearer, the more PAR and the farther, the low PAR.

Now you may ask how much PAR is like 4 WPG and what PAR is like 1 WPG. We started this hobby by learning the light in WPG. It’s same as learning the difference between rupees and dollars. You know $1 is 50 Rupees but still, being an Indian your mind is not tuned according to Dollars (Happening to me right now :/). So to tell you- 

10-30 micromoles of PAR- Low light
30-50 Micromoles of PAR- Medium light
50 and above- High light.

This photo explains it very well. See the green and yellow (500-600 nm) are the lowest points. Remember, they’re not ZERO. It’s not like plants DO NOT absorb Yellows and Greens. They do but very small in comparison to Blues, Violets and Reds. Red is said to be a helping hand in growing algae. So an ideal spectrum to use in the aquarium would have low Reds, Greens, Yellows and High Blues and Violets. You can keep Reds on the high notes but then you must have good CO2 and good fertilizers to keep up the balance.

 

 

 

 

LED

Now let’s talk about LEDs. I’m again reminding you that I am writing this at a very basic level. I won’t go deep into the semiconductor world. The info one needs to know to understand the LED lights for aquariums is all I want to write.

LEDs are very small lights. They have a positive and a negative terminal. They are very small to solder the wires on. So the manufacturers mount the LEDs on stars. This gives it enough space to solder the wires and to put the LEDs on the heatsinks. Size of the stars is generally 20mm.
The photos will explain it to you-
This is a LED.

Now let's see how a start looks like-

And when the LED is mounted on the start it looks like-

This would be the final product you would be getting. This is how the LED, we now, looks.

 

How Many LEDs to use for my tank?

When building a LED light unit for your tank, the first question comes to your mind is- how many LEDs to use. The rule of thumb says-

Numbers of LED to use = The area of footprint of your tank / 22.
 
Let’s say your tanks is 24”x12”x14” [LxBxH] the area of the base would be- 24”x12”= 288 sq inch.
Now to calculate the no of LEDs to use- 288/22= Around 13 LEDs would be needed.
 

What colors do I need?

White LEDs come in 3 colors-

• Cool White (Color Temp- 6500K),
• Neutral (Color Temp-5000K)
• Warm White (Color Temp- 3500K)

Don’t get confused between the wavelength and color temp. Wavelength is measured in nm and the temperature of light is measured in K Kelvin.
For planted tanks, generally we prefer Cool white light. But if you want to make a LED unit for your discus tank or fish only tank, Warm white would be the best choice as it gives the perfect yellowish color and accents the color of fish [Just like under our ‘Hitachi’ tube light, goldfish used to look pink ;)]
As we have discussed earlier, an ideal light’s spectrum would have low Reds, low Greens and Yellows and high of Blues and Violets.
So to mimic this ideal condition in our DIY-ed LED unit, we mix some colors with cool white. Like- Royal Blue which have the wavelength of 465nm to 485 nm.

Cree XP-E Royal Blue color parameters-

Or some Violet LEDs which have the wavelength of 410nm to 420nm.

Now let’s see the spectrum and the PAR data graph of some combinations of LEDs-

Cool White + Neutral White. As you can see the Greens, Yellows and Reds are quite high than the Blues and Violets.

Cool White + Warm White. Compared to the last combination of Cool white + Neutral White, this has much lows of Blues and Purples.

Now see the combination of Cool White + Warm White + Royal Blue. The Blues and Violets are very high and Greens, Yellows and Reds are very low.

Now guess what would be the best spectrum for your planted tank!!
Yes! You’re right. The last one, because it has low Reds, Greens and Yellows and has high Blues.
The one I’m gonna build would also have the same combination of Cool whites, Warm whites and Royal Blues.

How to practically build a LED unit.

You would need-
•    Heatsink
•    LEDs
•    LED optics
•    Power supply drivers
•    Fan for the heatsink (Optional)
•    Dimmer/ Controller (Optional)
•    Wire
•    Solder cable
•    Solder Iron
•    Thermal Adhesive or thermal grease.
•    2 AA batteries to test the LEDs

Heatsink- 
Prior to start telling you what it is, just see how it looks like-

It has a lot of fins or wings which makes its surface area way bigger than just of a solid piece or a plate of the same material. Generally Aluminum is used to make the Heatsinks. But now hard anodized heatsinks have also hit the market.
The black one shown above is hard anodized and the white one is just Aluminum heatsink.


There are 2 ways to mount LEDs on the heatsink-

1. Thermal Adhesive- It’s like fevikwik. Just put a drop of it on the back of LED and paste it. But the joint is permanent. You won’t be able to remove or replace the LED.
2. Screws and thermal grease- Drill the holes on the heatsink. Put some Thermal Grease on the back of LED and screw it down. We put the grease so that the heat from the LED can transfer to the heatsink already. Any air gaps could make your LEDs very hot and damage it.

Some people put fans on their heatsinks. How to know if you need a fan on your heatsink or not.  Just touch your heatsink when the unit has been on since 2-3 hours. If you can touch it, you don’t need a fan. But if you can’t touch it, you need a fan.

LEDs- 

LEDs have some characteristics. Like we buy our CFL bulbs by their wattage, we buy LEDs by their Forward Voltage and Maximum Drive Current.
Like- A Cree XT-E Royal Blue LED has Forward Voltage of 3.0 V, wattage of 3W and Max Drive current of 1500mA.
It means the maximum current you can give to this LED is 1500 mA and when put in a series, after every LED you’d see a drop of 3 Volts in the Voltage.
LED Optics-
 Most LEDs have a light angle of 120 degrees. Which means the light would spread in a cone of 120 degrees. So to concentrate the light over an area we would need some lens or optics. Optics are named according to their concentration capabilities - 20 Degrees, 40 Degrees, 60 Degrees, 80 Degrees.
Power Supply Drivers- 

LEDs work on DC current. So the drivers convert our household AC current to DC to light up the LEDs. They are characterized by their Max Drive Current and total Wattage.

For eg. Inventronics 40w driver - 700mA. Its total wattage is 40 watts so it can light up around 12 LEDs of 3W each. We leave 4 W as a margin. The 700mA is the Max Drive Current. You can use 700mA driver to light up a LED which has Max Drive Current rating of 1500mA. But you cannot use 1500mA rated driver to light up the LED with 700mA Max Drive Current.
Now, Just to talk a bit more about the drivers, lets take a new LED which is more efficient than the previous XP-G or XT-E. Cree XM-L. It has Max. drive current of 3000mA. It's upto you how much light do you want from this LED. If you put 700mA driver, it will give low light, Gradually if you increase the input current from the driver, the light output will increse. Lets see it's graph-

 

Dimmer/ Controller- 
Just like we have controller for our ceiling fans, you may put dimmer for your LED lights. These are nothing but potentiometers. Generally we use 10 ohm dimmer.
But if you want to go fancy (which I wanna go :D) there are sunrise sunset dimmers available. You may set the time when your LEDs will start lighting up from 0% and when they would go 100% and the same of 100% to 0%. A lot of options are coming in the market nowadays.
See the one I'm gonna use here- dimmer youtube video
Wires, Solder cables, and Solder Irons- 

You all know what their uses are.

Before concluding the bibliography, I'd like to answer the question which still is buzzing in your mind(yes, I know it all ;) )- "How does a finishe LED light unit look like ?"

So, check this vid out and you will come to know- WIfe approved DIY LED unit 

 
I’ve read this information in past months from the following links and I thank them all. Specially Milad from ledgroupbuy.com, Hoppy from TPT, redfishsc from TPT, the blondskeleton from TPT.
•    http://www.plantedtank.net/forums/showthread.php?t=182365
•    http://www.plantedtank.net/forums/showthread.php?t=136519
•    http://www.plantedtank.net/forums/showthread.php?t=184368
•    https://www.youtube.com/user/ledgroupbuy
•    http://makersled.com/
•    http://www.ledgroupbuy.com/
•    http://www.rapidled.com/

This article is written for the sole purpose of understanding LED lighting solutions for aquariums. It is based on what I have read and learnt from various sources. In case something goes differently or unxpected, I am not responsible. All the links that I have read to write this article are mentioned. All the photos are either from the internet or from the links that I've posted. They are the property of their actual awner. I've posted them here just for the information. In case something is not included, please let me know and I will include it.
Thank you for reading this. In case you see something wrong in here, please drop a comment and I'll update it.

The next blog I wrote after this blog can be found here-
Link on TPT
 or 
Link on Instructables.com

Trip to Pench National Park

 

I was the last person who was informed about this trip, because neither my friends nor I was certain
about going. My friends weren’t sure because I was in Bangalore for a long time, and I wasn’t because
I had bigger and important things on my mind at that time. I don’t know who among all of them came
up with the idea of this little adventure, yes adventure, because it was, and even before it started,
it sounded like one. Then when Naman and Piyush went and actually booked a resort and a safari, it
occurred to me I was going. 22nd was the chosen date. The trip was planned for 10 friends for a single
day. As most of them were businessmen, they wanted a short and sweet trip. So it was just a one day
trip.

We departed from Raipur on 22nd in the afternoon, arrived at Nagpur in the evening, reached the
resort at Pench National Tiger-reserve Park at night. Our plan was to stay overnight and then go for a
morning safari. After the safari we would head back home. Everything was set. The trip started. We had
an awesome dinner at the MP tourism Resort where we were staying followed by some fun and beer.
We had one more reason for this - It was Piyush's birthday that day. After our late night photo-shoots
and masti we all slept at around 2 and woke up at 5 in the morning. We got ready and our gypsies were
ready to take us to the deep forest.

Just to tell you, Pench is a National tiger reserve which lies in Maharashtra and Madhya Pradesh. The
area is around 750KMsq but the area opened for tourists is just 20% of the total reserve. It has 33 tigers,
40,000+ spotted deer, 30,000+ peacocks, 350+ varieties of birds, and many other animals. The forest is
mainly made up from Teak.

So our gypsies started running towards the jungle. We completed formalities at the entrance and
entered the Pench National Park. Now let the photos speak for themselves.

The first thing we saw was an owl. "King of camouflage" It was so wonderfully blended in the tree that it
took us 5 minutes to spot it. There were 2 of them.

Then there were many many peacocks and hundreds of spotted deer.

As we kept going deeper and deeper our guide was trying to keep our expectation levels low by
continuously telling us that no tiger has spotted in last 10 days. So, there was very few (or no) chances
of spotting a tiger that day. Then we reached a lake and our guide noticed some markings on the road.
And it was a tiger’s footprints. But then he said that the tiger has crossed the road and went towards
the forest which is out of bounds for tourists. Again our hopes crashed. We kept moving forward and
spotted some wild boars along the way.

And as we moved further, our driver suddenly stopped. He was trying to hear calls (Monkeys and deer
start “calling” out to other animals as a warning if they see/ feel the presence of tiger). Then he showed
us fresh dropping of a tiger (dropping = potty). That means the tiger was there 15-20 minutes ago. But
again our guide told us to keep our hopes low as it again went in the jungle. Then we again moved
further. Other gypsies moved in other directions. Our guide asked our driver to go to “Hand-pump”.
They’ve named the areas inside the vicinity. And as we were on our way to that Hand-pump, our driver
said- “Silence…a Tigress”.

And we were all awestruck. She was coming towards us in a slow majestic walk. I started clicking her
every step. I took 88 photos of her in just 3-4 minutes. She came and stood near our gypsy as if she
was giving me side pose, her feline body shining shades of orange yellow and black. I clicked her till
my photography instincts were saturated. And then she slowly disappeared into the jungle. It was an
awesome feeling filled with both fear and excitement in her presence. As she went deeper and deeper,
we couldn’t see her, but animals started calling out. On our way back we saw jackals and many other
birds. The trip ended with a feeling of utmost content, we were now going home with a once in a
lifetime experience.

Dawn at Pench.

The Team

Roads to the Mowgli Land

"King of Camouflage"

"Indian Scops Owl"

Spotted Deer || The bigger the horns, the better the girlfriend ;)

Their Antlers Shed

And they get new beautiful Antlers :D

Eye Contact

Peacock

Changeable Hawk Eagle

Indian Ringneck Parakeet

Indian Roller

Pied Kingfisher

Basking Bird

This lake is the main water source to the animals

Tiger's Footprint

This is how a tiger marks it's territory. It pisses on the tree trunks. Unlike most animals, their urine leaves a characteristic yellow mark.

The dropping tells many things. The hair you can see in the photo tell us that the last hunt of this tigress was a deer. And the hair come out when the dropping is the last digestive remains of that kill. It means she's on hunt again. And the freshness tells the time when she was there.
It's of great help.

Tiger scratches tree trunks. Some say they do this to sharpen their nails while some say they do it just out of aggression.

This was the time when I first saw her.

And she started coming closer.

She has a collar on.

She was walking straight to us.

She was wonderfully resplendent.

White dots on her ears look majestic.

They spray their urine on tree trunks to mark their territory.

A monkey was shouting out loud. She just gave him a look and monkey fainted :P

"Jackal"
Jackals of Pench are the most colorful ones in India. And unlike the Jackals of other parts, they hunt also.

Birthday Boy Piyush.

Wild Boars.

Reading this may make your train journey easy.

Festive season and summer vacations, these were the times when doing reservations in trains used to be tough. But nowadays, all 365 days are the same. Getting a confirm berth is becoming like bringing a piece of meat back from a tiger’s mouth. In last 18 months I’ve travelled a lot. And in these 18 months I’ve been through a lot. So just want to share some tips and tricks which I’ve learnt the hard way. Reading this may make your journey a bit easy if not completely.

I won’t say that you should plan your journey at the earliest, because that isn’t possible. Courtesy - our lifestyle. So let’s assume, you want to go somewhere next week, after 10 days, that gives you 10 days to plan your journey. Now when you open your IRCTC account and try searching for a train, every train you see is full. Some are showing regret and some are showing the numbers that you know can’t get confirmed. But still you see a train which has the least number of waiting- maybe 7 or 8. So-

1. Chances of clearing of a waitlist number in AC 2 are least. Then AC3 is second and then Sleeper. It means, Sleeper waiting list has fair chances of getting cleared. Why? Because whenever the waitlist is full and the status is showing Regret, it means there are enough people in the waitlist who can fill 1 or 2 complete coach/ bogies of 72 seats each. So if the division which is running the train has extra sleeper coach (which they generally have), they will put in the train and your ticket can get confirmed. But usually they don’t have extra AC coaches. So chances of your ticket getting confirmed are quite rare in AC.

2. I didn’t say AC1 in the last point, because it’s better to take a flight than to travel in AC1. Charges of AC1 are quite equal to domestic flights if you make your reservations 30 days prior to the journey date.

3. There are many people who say they can get your ticket confirmed by putting it into VIP quota. They are just bluffs. It’s true that there’s something called VIP quota but that has a very small number of births in trains. So chances of getting your ticket confirmed by VIP quota are very rare (until and unless you know a VIP personally or you yourself are one LOL).

4. It just happened accidently. I was trying to get a ticket in Tatkal quota by logging in the IRCTC website at 10 in the morning. And if you’ve ever tried doing that, you would know how big pain in the butt that is. So I tried doing transactions 2 times. Money was getting debited from my account but the website kept saying “You’re session has expired”. I was so irritated and suddenly a friend of mine called from USA. And I asked her to open the website and to do all the steps. And to my amazement, everything was happening very fast. And she didn’t face any problem at all. Maybe it’s because the servers of our internet providers get coagulated with the requests for IRCTC. But if it’s really urgent, ask a friend living abroad to help you.

5. PQWL- Well this is a point which can boggle your mind. We all are acquaintance with GNWL (General Wait List). Generally if you buy a waiting ticket, it has got GNWL written on it. But there’s one more thing- PQWL (Pooled Quota Wait List). Understanding PQWL maybe a bit tricky. So read it carefully-

Suppose you want to travel from Bangalore to Nagpur and there is a new train 09308, Yashwantpur- Indore Special (YPR- INDB SPL). When you check on IRCTC, YPR to NGP, it shows 6 waitlist (It’s not specified there, GNWL/PQWL) in AC 2. You go ahead and book the ticket which is at waitlist 6. But then when you check the same train from YPR to INDB (INDB means Indore which is the destination of this train), there are 16 seats available. WHoaahhh !! Then what was that?? Just few minutes ago, it gave you waitlist 6 ticket and now there are 16 tickets available. How’s that possible.

Let me explain this to you- This train starts from Yashwantpur and goes to Indore. You were trying to book ticket from Yashwantpur to Nagpur. Nagpur is like somewhere in the midway. So, if you will get a confirmed ticket from Yashwantpur to Nagpur, who would pay for that seat after Nagpur all the way to Indore!! It would be the loss of railway. This diagram would explain it to you- 

The fair between YPR- NGP is 1800 and between YPR and INDB is 2500. So if you take a birth from YPR to NGP, you would pay 1800 Rs. But what if there’s nobody to sit on that birth after NGP !! So, instead of giving you the birth, railway put you in PQWL. Now there are 2 cases-

(A)-They wait for a person who is willing to go to Indore, because he will pay 2500 Rs.

                                                            OR

(B)- If a person wants to go from Nagpur to Indore, then you both would be paying a sum of 2500 Rs and the seat would be acquired the whole way.

So, ultimately you can say that GNWL has higher priority than PQWL. And whenever you try to book a ticket and see waitlist, don’t forget to check the availability of the tickets till the destination. It may cost you more, but it’s far better than taking the pain of doing tatkal reservation and dealing with those agents.

6. Now if you’ve to travel and you don’t have reservation (or may be waiting in sleeper). Here’s what you can do-

S1, S3, S5, S7, S9, S11…..   The sleeper bogies, with odd extension, have 1 birth reserved for TC (Ticket checker). Birth number-7. You can ask the TC, and can get that seat. It depends on your convincing skills though ;). Especially, it really helps while coming to Multai from Bhopal or coming to Raipur from Nagpur.

#All of the above information is based on my experience and my knowledge. It’s up to the reader to understand it and follow it, if he wishes to. But if something goes different from what is stated above, I am not responsible for it. This is just my blog post.

Some questions this blog answers:

Reservation in AC1, AC2, AC3 and sleeper class?
What is waitlist?
What is PQWL?
What is GNWL?
What is VIP Quota?
Reservation problems in using IRCTC?