Fluval Sea Nano 20W Seneye PAR and PUR Channel Characterization

[Big Mistake]

Here are some Seneye PAR/PUR charts for a Fluval Sea Nano 20W light.

It is on a Waterbox 10 gallon.

For these measurements the light was 7 cm (2.75 in) above the water and the Seneye monitor was 15 cm (5.9 in) under the water.

So, the Waterbox 10 gallon is 14 inches tall so the sensor was 7 inches from the bottom and the light 1 inch above the lip.

Sort of the middle of the tank.

Seneye monitor directly under the light with the Seneye held fixed by a fixture.

Pumps were off so the water would rise by 2 cm when circulation is in effect.

Each screen shot has a notation but basically each channel individually at 100%. Cool White was sampled alone at 50%.

And all channels at 100% and what I am running with Pink, Cyan, Purple, Blue at 100% and Cool White at 50%.

It is the black curve that shows the response of the light against the Seneye PUR spectrum of the light used by plants (corals).

Notice some of the channels report 0 PAR even at 100%. Don't know if that is the light or the response of the Seneye.

Won't speculate about what these show beyond that as it would largely be a belief and not data.

Do the corals like the light? Unfortunately I don't speak coral.

When the lights are just 1% blue and 1% purple the corals do fluoresce nicely. I wonder if they do that to attract prey?

-Big Mistake

 

[ingchr1]

Interesting on the readings for individual LEDs. You are getting LUX and PUR values but no PAR. Would like to hear the light experts view on that.

Here was the measurement I got on my Waterbox 15 with the Seneye on the sand bed, all channels at 100%.

 

[Big Mistake]

The low PAR numbers are because those LEDs are very low power and many fewer pink than cool white. If the Seneye is held close to the light it will show PAR. I will scare up those numbers.

Odd thing I have with the Seneye will not show the PUR curve until it goes into salt water. Even freshwater does not work.

But once it starts, it will work fine, in or out of the water. I need to ask.

Here are some more results; Incandescent light, dim and bright, UV LED flashlight new batteries, White LED flashlight old batteries. Seneye held close in call cases. Notice the large variation in PAR.

Like to get it outside on a bright clear low humidity no haze sunny day ... I assume the PAR/PUR of the Earth's Yellow Sun is well documented and would work as a good reference.

Don't know if the flashing red out of water sensor/indicator is perturbing the results say for example the UV flashlight.

-Big Mistake

 

[Big Mistake]

Natural sunlight through a glass window facing South (on a poor day for Sun Spectrum measurement since it is Nov 14th at 10:00 am and the Sun is relatively low on the horizon with different light scattering compared to directly overhead.)

Need to wait for a better day, maybe tomorrow. June 21st in Colorado at Solar noon would be even better.

White flashlight needing new batteries is very close.

Web image of July Sun Spectrum in Fiji for comparison.

PAR and Kelvin are pretty close if what is on the Internet can be trusted ...

-Big Mistake

 

[Big Mistake]

So what is the conclusion of this thread?

The assumption that needs to be made is that the spectrum of the Fluval Sea Nano 20W is suitable for growing coral.

Hard to know without a laboratory grade spectrometer, learning to scuba dive, fly to Fiji, and swim down to measure PAR and PUR on some nice corals.

Under that assumption, a Fluval Sea Nano 20W makes a perfectly fine light for a Waterbox 10 gallon.

Running Pink, Cyan, Blue and Purple at 100% and Cool White at 50% will produce PAR levels around the edge of the tank at the bottom glass of something like below with the light 1 inch above the lip of the tank. Some data points are interpolated due to the current space aliens inhabiting the tank.

79............79

104............104

71.....100....71

Should be able to have a SPS frag on the back wall rock near the top.

Prior to the Seneye I assumed Pink was Red, and Cyan was Green and had them at 0% in a Bulk Reef Supply approach.

But now I am running Pink, Cyan, Blue and Purple at 100% and Cool White at 50% using Tropic Marin Bio-Actif for the higher alk and grocery store distilled water.

Light schedule is 2 hours ramp up, 7 hours full, 2 hours ramp down, and 2 hours in the evening of blue and purple both at 1%. Once the Sun goes down the tank is nearly full dark all night.

I acquired the Seneye under the assumption I would have had to rent a PAR meter twice.

That the Fluval Sea Nano 20w was going to show very low PAR, I would have to buy a new light, and hence two rentals at ~$60 a pop.

Probably my big mistake was buying a frag pack from WWC and waiting for a single polyp coral to grow out and not visiting a couple of my LFS on a regular basis as their stock waxes and wanes. But I have corrected that.

Now if I can just get the Hammer coral to eat some shrimp or salmon.

I miss the Neon Tetra hamburger and salmon induced feeding frenzies.

-Big Mistake

 

[Hooz]

I'm currently running this light on a Fluval Flex 9 with all softies (Zoas and mushrooms) and all of my corals seem to be doing fine. I run similar settings to you (Cyan, Violet, Blue and Pink at 100% during peak and White at 50%). In the evening I have White and Pink go off before the Blues and Violet just so I can get a good "viewing window" to really see the colors for the last 2 hours before lights-out, which brings me to my last point...

I think the reason the light gets such a bad rap is because you HAVE to run the whites so high to get decent PAR. Yes, I have the whites at 50%, but there are more white LEDs in this light than all the other colors combined, so 50% white is still really white color-wise. I mean, it will grow corals, they're just not much to look at during the day (basically just shades of brown with no "pop").

I really like the programability and controls of the light, but I'm switching this tank over to a Kessil A80 Tuna Blue so I can get the color that I want (dialing down the white) without losing the PAR the corals need.

 

[Hooz]

To go with my post above... My schedule, and pictures of a zoa colony at peak light and during my evening "blues only" viewing window (through an orange filter).

 

[Big Mistake]

One thought I have, but not acted on, is to have two of the Fluval, for less cool white, better "blue par" and even better coverage.

Makes the assumption that the non-cool white spectrum, especially the deep blues, line up with classic source like T5s known to grown coral.

-Big Mistake

 

[Hooz]

I thought the same thing. I was thinking about getting the Flex 32.5 and adding the second light, not so I could have all the PAR of the strips combined, but so that I could have more blues and less white and still get the PAR I'd need.

I scrapped that idea, though. Ordered an IM 30L and a pair of AI Prime 16HDs instead.

I do like the little Fluval light, though. I think I'll find a cool use for it somewhere. It's been growing my Zoas just fine in my 9g nano, so I know it's a capable light.

 

[Scottrshoe]

I know I am resurrecting an old thread here, but I have this light on my IM NUVO 20 Pro, and do not have a PAR meter at my disposal.
I have used the FW version of their lights for years now, and I really like the way they function, and the price is reasonable. Which is why I bought one when I ordered my tank.

After reading some bad reviews of the light, I did the only reasonable thing, and ordered another one! My concerns were that it would not be powerful enough to grow corals throughout the tank without running the whites super high. To my mind, having a second light would spread the coverage out, and the overlap would increase the PAR in those areas as well. Is this sound logic? I don't intend to grow SPS in this tank, but also do not want to run my whites high all the time.

Anecdotally, I think the lights look pretty slick with their low profile, and swing out mounting arms.

 

[Hooz]

I know I am resurrecting an old thread here, but I have this light on my IM NUVO 20 Pro, and do not have a PAR meter at my disposal.
I have used the FW version of their lights for years now, and I really like the way they function, and the price is reasonable. Which is why I bought one when I ordered my tank.

After reading some bad reviews of the light, I did the only reasonable thing, and ordered another one! My concerns were that it would not be powerful enough to grow corals throughout the tank without running the whites super high. To my mind, having a second light would spread the coverage out, and the overlap would increase the PAR in those areas as well. Is this sound logic? I don't intend to grow SPS in this tank, but also do not want to run my whites high all the time.

Anecdotally, I think the lights look pretty slick with their low profile, and swing out mounting arms.

You are correct. You have much more "headroom" with 2 strips. Makes it a much more flexible option.