Light Reflectors - Double The Light?

[kevin82]

Using a light calculator I found on the net, my tank setup is deemed to produce low light. Wanting a planted aquarium this is limiting my plants.

I have a Fluvel Roma 125L fitted with 2 x 20W T8's.

My question is do light reflectors really double the light output from a tube, as stated on all reflector manufacturers boxes?

 

[Squid]

I think double is a little ambitious, but they do help.

 

[angelfishguy]

ive been told that with reflectors it does increase your lighting more then without them
but with them the highest about of light you can get is 40watt with the 2 bulbs. reflectors just stop light being wasted

 

[kevin82]

It's a strange thing because it's not something you can measure once they are fitted

I think I'm going to have to get them because as mentioned, it stops light being wasted and lets face it, there isn't much to start with my "low light" setup

 

[VaegaVic]

All reflectors do is stop any light from being wasted.
If a circular bulb gives out light, it gives it out in a complete 360 degree angle. Reflectors take the 180 degrees not being used and reflect it back towards the tank, effectively doubling the output already in the tank.

However, it does not increase your WPG as that is still based on the wattage of the bulb.
All reflectors do is just insure that more light out of the total amount, is being used.

 

[Truck]

No way is 2*20 watt T8's running the length low light, its actually very high! you could grow anything with CO2, and as people have previously posted, reflectors ensure that all light is utilised, and that non is wasted, it does not double the output.

 

[Squid]

I wouldn't class 40 Watts in a 33 gallon tank as "very high". It's usually referred to as low-medium.

Squid

 

[Truck]

The WPG rule was based on T12 tubes, and these are T8's so what would normally would be Approximately 1.3WPG is now 1.95WPG because T8's produce about 50% more light than a T12 tube, 1.95 WPG is near enough 2 WPG, and will grow anything with the addition of CO2, 5WPG is no longer needed to grow plants like Hemianthus callitrichoides. Anyone with that kind of light may struggle to grow plants without Co2 addition, algae will soon take hold if the photoperiod is not managed properly.

In the eyes of UK aquascapers 2WPG is quite high, Low light IMO is about 1WPG.

 

[Squid]

The WPG rule was based on T12 tubes, and these are T8's so what would normally would be Approximately 1.3WPG is now 1.95WPG because T8's produce about 50% more light than a T12 tube, 1.95 WPG is near enough 2 WPG, and will grow anything with the addition of CO2, 5WPG is no longer needed to grow plants like Hemianthus callitrichoides. Anyone with that kind of light may struggle to grow plants without Co2 addition, algae will soon take hold if the photoperiod is not managed properly.

In the eyes of UK aquascapers 2WPG is quite high, Low light IMO is about 1WPG.

I would still class this nearer to medium, even after reading other forums such as UKAPS. I was mainly referring to your comment about it being "Very High", which whether it's T8 or not is not quite accurate.

 

[Mikaila31]

Reflector do indeed help. You can use simple tin foil or aluminum sheet roll to make a cheap reflector.

You tank has low-medium light at 1.2wpg of T8s. You can grow a number of plants in it with the current light levels. No CO2 necessary.

I've run tanks with 2wpg with lights on for 10hrs+ w/o CO2 using T8 bulbs, it was my most algae free tank and least maintenance. IMO 2wpg is a great amount for a medium light tank. For the last 2 months my 20gal has been running almost 3 watts of power compacts w/o CO2. Its no worse than before the CO2 broke......

 

[Dave Spencer]

It's a strange thing because it's not something you can measure once they are fitted

It actually is possible, with a PAR meter. A fair amount of measuring has been done recently, and it turns out plants don`t anything like the amount of light originally thought.

Dave.

 

[J4G3D]

I bought some plastic white piping from b&q to boost the lighting in my tank.

Makes a difference but minimal. For the sake of £2 for the pipe i had to try it.

 

[aaronnorth]

Even when reflectors are used, there is still some restrike back onto the tube so 100% of the light is never utilised.

 

[iliveinazoo]

Even when reflectors are used, there is still some restrike back onto the tube so 100% of the light is never utilised.

+1,
Also the light that is reflected back down into the tank will be less intense due to the increased travelling distance. You obviously still get more light for your money though.

 

[lljdma06]

The WPG rule was based on T12 tubes, and these are T8's so what would normally would be Approximately 1.3WPG is now 1.95WPG because T8's produce about 50% more light than a T12 tube, 1.95 WPG is near enough 2 WPG, and will grow anything with the addition of CO2, 5WPG is no longer needed to grow plants like Hemianthus callitrichoides. Anyone with that kind of light may struggle to grow plants without Co2 addition, algae will soon take hold if the photoperiod is not managed properly.

In the eyes of UK aquascapers 2WPG is quite high, Low light IMO is about 1WPG.

UK aquascapers, Mr. Truck? If I recall correctly, I was doing low-light way before you were. Eh, 1WPg is medium. Now, .5WPG, that's low.