- Today on BRStv,
lighting's both the most commonly
mis-installed component on the reef tank,
but also, paradoxically, the easiest thing
to get right the first time.
If you want to see how a par meter can realize that dream
of getting it right and knowing it, that's coming up.
(upbeat music)
Hey, this is Ryan with BRStv's 5-Minute Guide
Miniseries on LED lighting on reef tanks.
Our goal is a few minute path to solving
those lighting challenges forever.
I'll just start by saying
you're not alone, if you've struggled with lighting,
or actually just find yourself wondering
if you've done it right,
this is something almost all of us have experienced
at some point.
I'm just gonna say it like it is.
Most of the discussion about reef lighting's
a million miles from clear,
very little is universally agreed upon.
And what little there is,
is simply not transferrable from one tank to the next.
Today, we're gonna get past all of that.
Show you a way that will produce reproducible, legit results
for anyone who chooses it.
All based on tens of thousands of par measurements,
our own results, and the numbers the pros use
to achieve their success.
The approach is based on using a par meter
as a tool to measure light output
and make informed decisions
that lead to reproducible results.
Most of the corals in our tanks
have fairly well agreed upon par ranges
that they thrive in, so let's use 'em.
That said, there are two approaches I'll share today.
The easy way most reefers use
and then the advanced approach.
Both will get you where you need to go,
but there's some pretty serious advantages
to putting just a little bit more thought into it
with the advanced approach,
which will become clear in just a moment.
The easy route is this.
If you haven't already,
mount the lights the way the manufacturer suggests
and then adjust the intensity sliders or knobs
to your best guess for the corals that you wanna maintain.
It should be pretty obvious that the guess path
will only work with the experienced or lucky.
For everyone else, rather than just lose corals,
we can use a par meter to measure
how successful that approach was
and then tweak the settings so it's just right.
You can buy a meter if you want, but unless you have a
slew of tanks planned or advanced uses
like testing frags for color and growth
and different intensities, or have friends to loan it to,
it's just a lot cheaper to rent one.
We have them for $70 for a week with a free return label.
To do that, I suggest taking a picture of the tank,
then assemble a probe rod, hit the power button,
and start writing down some par numbers
at various locations in the tank.
The goal is simple.
If you have LPS corals like
Polyps, Softies, Micros, Acans, Zoanthids, Xenia, Torches,
Hammers, Frog Spawn, Toad Stools, Sinularia, GSP,
or any of these that just do best
with the BRS-recommended par range of 75-150 PAR
in as much of the tank as possible.
If you have SPS corals like Acros,
the BRS-recommended par range is 200-350 PAR
in as much of the tank as possible.
It's just the goal.
It's simple as that.
If you want a mixed tank,
well, not surprisingly, you're gonna have to create
some zones of 200-350 PAR in areas
and other zones, the lower 75-150.
However, for most people,
it's less about creating that area,
and more about just using the meter
to optimize the dominant goal,
like SPS up top, and then using the meter
to locate lower par areas for your LPS.
So that's where this stops for most reefers
and I'm pretty certain you can already see
why this method has higher success rates
than the slide and pray approach.
This is where the advanced approach comes in.
Most LPS tank owners will not need to take this step,
but many mixed tank or SPS reefers will benefit
from a more advanced approach.
A blanket of even light.
It's just more beneficial with these types of corals.
Some of you are gonna find that,
no matter how you move the sliders around,
there's always a giant hot spot in the center
of 600-800 PAR, but six inches to the right,
it's just 100-200 and the sides of the tank are like 25 PAR.
Finding this is actually great news,
because you just found what I would call
a fatal installation flaw that you'd likely never find
without a par meter,
and no amount of sliding will fix.
This is related to the fact that the manufacturer's
suggested mounting and spacing suggestions
can range from accurate to widely inaccurate.
Or, at least in your case,
not producing the desired results.
Most notably, just because it comes with legs
does not, in any way,
mean that the legs are the ideal mounting height.
In fact, we find it's far from that, in most cases.
So the solution
to the otherwise unsolvable hot spot, is simple.
Raise the light up and redistribute the light more evenly.
For those of you who want to take this advanced approach,
this is what we do here at BRS.
First, if Randy's done a recent Investigates on your light,
go look it up because it probably already has
all the work done for you
and has a data-backed recommended mounting height.
But without that,
I'd start by using the manufacturer's suggestion
as a starting point, and then, measure the top of your tank.
The top of the aqua scape
and where the top layer of corals are gonna be.
Ideally, looking for most of the measurements
in your desired coverage area
to be within about 100 points, or so, of each other.
If that's the case, move on.
The mounting height is good.
However, if you're getting readings of about 800-1000 PAR
and 100-200 PAR six inches to the right or left,
it's time to start raising up the light.
The easiest way to quickly assess
a decent mounting height above your tank
is just by raising the light above the tank
until you see significant signs of light spill
outside the edges of the tank.
Something you can often see on your hand, pretty easy,
will likely be within eight inches
and 24 inches off the water.
Where you fall in the eight to 24 inch range
is somewhat about the area you're covering.
Smaller areas can have the light closer to the tank,
larger cover areas benefit from raising the lights up
to achieve a wider spread.
But this is actually equally about the type of light used,
blending the spectrum from dozens of tiny LED diodes,
and redistributing the light evenly.
Ideally, in a blanket of light in the tank,
is a significant engineering challenge.
The closer you get to water, the harder it is to do well,
and relay that, the more costly LED fixtures
often provide the best performance in this area,
and can be mounted closer to that eight inch range
and still provide that even blanket of light.
That said, you can often get similar performance
from the intermediate to lower cost LED options
just by raising the light up higher.
In the end, it's all in the numbers,
so just check with the par meter and confirm
that it produced the desired even spread.
Might take a few height measurements to get right,
but with a par meter, you can confirm it,
and you should be able to find that optimal height
within a matter of minutes.
There are often some efficiency losses
from the highest mounting heights and,
viewed from a sitting position,
it might be somewhat blinding,
but when you do find the right mounting height
for your specific height,
you'll likely find watt-for-watt,
the par output and distribution
between many different light brands
are in the same neighborhood.
That's the goal of find the right mounting height.
Not just the right tool for the right job,
but also, installing a tool
to achieve it's optimal performance.
Next up is using the par meter as a tool
to identify ideal proper spacing of multiple modules.
At first glance, it would seem like spacing lights evenly,
over the tank, would produce even distribution.
However, the reality is,
the light sources intersect in the middle,
producing a hot spot,
which is often 50% higher than the sides of the tank.
You can solve this by moving the lighting
out an inch or two, towards the sides,
and measuring again.
Proper spacing does sem to be much more important
when you use a couple of really high-powered lights
to cover a larger area,
like two in a 120 gallon tank,
but matters less when you use, say,
four lights with half the overall wattage,
to cover the same area.
In either case, play with the spacing a bit,
confirm with the meter,
and you can hone in on some ideal parameters for your tanks
in a matter of minutes.
Once you've found that ideal height and spacing,
we just go back to the Easy Pad,
take that photo of the tank, and write down the par numbers,
and adjust up or down, til you get that ideal coverage
for your desires.
Again, the BRS-recommended range for SPS being 200-350
in as much of the tank as possible.
If you have LPS,
75-150 PAR in as much of the tank as possible.
One of the things we're doing to make this easier,
is Randy's doing most of the legwork for you
with BRS-recommended mounting height, spacing, and settings
for a ton of different lighting options,
with a new one each week.
So I'd check out this playlist right here.
There's also a hot link to the par meter rental right there.
They're often on sale, so I'd check it out.