# The new LED bars Orphek OR2 Reef Day Plus tested in our DaniReef LAB

## How to value these numbers in aquarium?

This is a good question. At first we thought that we could transport these values to the aquarium tout-court. Than we filled the aquarium, insert the probe and redone the measurements. We fazed but, as we have already said in elsewhere, we’re going to talk about this in another article. Basically, while at 20 cm the result is practically the same, as we progressed, thanks to the glass and the water itself reflecting the light, we found even the double of the values measured in air. Obviously this isn’t a detail that can be standardized, so we think that our method of calculation is the most correct, and the best for the comparison of coverages of different ceiling lights.

## Consumption

The measurement of the consumption was made possible thanks to the useful device RCE PM600 that can also measure the Cos(fi) (or power factor). The result is already given in watt.

Here above there’s the maximum power and below the Cos(fi).

The calculus of the absorbed current, that is the power, is the following one:

Ceiling light Orphek OR2 Reef Day Plus: 54,69 watt. Considering that at 17 cm the bars have at the middle 393 μmol m-2 s-1, let’s say, in perspective, that it will have a peak value of 7,18 μmol m-2 s-1 w-1 (PAR per watt). It’s hardly comparable with another ceiling light because it remains costant all over the length.

The consumption is slightly under the declared one, while the Cos(fi) is very close to 1, a perfect value.

## The comparison with other ceiling lights on the market

Recently we started to use the new Apogee’s Quantum Meter MQ-510.

But considering the first celing lights we managed to test we can do an interesting comparison about their produced energy:

The energy produced by each watt stays costant in the different distances in the Orphek OR2. A very good and linear behavior of these LED bars. Now we only have to measure the behavior of other LED bars in order to compare the results.

## Mantaining costs

The Orphek OR2 Reef Day Plus LED bars cost 180 dollars, plus the taxes we have to pay because there still isn’t a distributor here, but we have to consider the change of currency so, more or less, it’s the same price, that is 180 euro. The shipping is included.

The absorbed power is 54,69 watt, so the relationship cost/watt is about 3,3 euro per watt. In order to do a comparison with the other ceiling lights we had in our hands you can consult the following chart:

The celing light is excellently built, solid and very well assembled. I really like extruded profiles as well as the refinement. It’s very easy to use and you can combine more bars in order to obtain the power you want. Considering that we’re talking about a LED bar the comparison with other ceiling light is very pitiful. But if you consider the total amount of energy you can have the full picture, because the light has to be summed. So the bars are perfect for any coral, you only have to combine an higher number of models. Do you want to double the PAR? Use two bars. Or quadruple? Use four, and so on. The cost per watt is very low, the lowest we’ve ever recorded, while before saying anything about the PAR per watt we should have more bars.

Questions and comments, as always, are very welcomed.