Review: Arcadia Classica OTL-LED lights


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New lights continue to come into the office thick and fast and most recently from well-known and trusted brand Arcadia, writes Jeremy Gay.

This one is the new version of the universally popular T5 Luminaire, at least to my mind anyway. Arcadia do have an uncanny knack of producing LED lights that mimic existing lighting technologies like T5 and metal halide, both in colour and punch.

The OTL-LED comes in freshwater and marine versions and ranges in size from 620-1820mm. Both marine and freshwater are fitted out with a combination of 1.5w and 10w diodes, the freshwater including RGB, 8,000K and 10,000K; and the marine, blue, RGB and 14,000K. The result is that these lights are incredibly bright — brighter than you could ever possibly need.

To give you an example I compared a 62cm/24.4" freshwater unit to a 150w metal halide with a freshwater bulb, and I had to dim the OTL down by two thirds to match the PAR output of the halide! I took the halide off a planted tank to swap it for the now dimmed down OTL, and within 15 seconds of putting it on the plants started pearling. So there is definitely something in those freshwater LEDs, in terms of spectrum, that the plants loved.

The unit itself is slimline, modern and comes with both length adjustable (and fully legal I might add) tank rim mounting brackets and a width-adjustable hanging cable kit, so you won’t have to buy any extra fittings.

A unique feature is its controller (also supplied). It splits the rows of LEDs in the unit into four, giving you four channels of control. Sunrise and sunset fade-in and fade-outs are actually preset to happen 30 minutes before and 30 minutes after your set ‘on’ times, although I prefer to control my own ramping up and ramping down.

Each of the four channels can then be set to come on for your required length of time, and the unit as a whole has adjustable brightness increments from 0-24 and the unit comes with built-in digital thermometer and temperature sensor — something I haven’t seen before on a lighting controller.

I only used it a few times but I didn’t find the controller that easy to use. We live in a world of intuitive smart phones and compared to my iPhone, which can second guess my every thought, the Arcadia controller was clunky and I still haven’t yet got it do what I want it to.

It could do with a demo function too, as otherwise you have to go through an actual 12-hour lighting cycle just to see when each channel comes on and goes off. The light unit’s external colour is Arcadia corporate silver, although I prefer black or white. I was using silver Arcadia lights over a decade ago.

On the box Arcadia has branded it as Classica, which I consider to be Arcadia’s value brand, but I would elevate it to full Arcadia status. The paint on the mounting brackets was a bit tacky on my model, but I’m always one of the first to receive products and that may improve as more models are rolled out to the mass-market.

Arcadia also says that the marine unit is fine with soft corals, sponges and invertebrates, but I think it's are playing it down. You could easily light the most demanding of corals with these and at depth. As I say those PAR readings were through the roof and, if anything, you’ll be turning these down, even for Acropora.

With all those RGB LEDs in the freshwater unit, with all channels on equally, the overall hue was a bit pink for my taste and as soon as I work out how to program just the 8K and 10,000K diodes to come on by themselves, I’ll be doing that. The hue was very 4 x Arcadia T5 of the past in colour, so it will make a nice transition for existing Arcadia T5 users, yet with much more brightness, light punch and depth like you get from a metal halide.


With so many lights coming into the PFK office we were in serious danger of becoming complacent, but this unit did make me sit up and take notice.

If I had a planted aquarium or a reef tank and wanted a good value, complete lighting package delivering control, colour and brightness, I would seriously look into these.

Price: RRP from £299.99 (620mm) to £699.99 (1820mm).

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