PAR meter to borrow?

I know the club does not. I don't know of any members that have one.

Par meters don't give you an accurate number of actual value but they will give you a valid level of change in intensity. If you want an accurate measure of LED light output you need to measure PUR. Most newer meters can measure both but this all comes at a price.

Start low and make small adjustments each week until you see a negative reaction (pail colors or polyps not reacting as they have before) in some corals. This is a sign that it is too much. Back it down a little and let it ride for a while to see the effect over time.

I generally adjust on a Saturday morning so that I have the weekend to observe the tank immediately after the change and be able to adjust back down if it's too much. That's better than adjusting in the morning and then going to work for 8 hours only to come home and find everything sunburned.

Fatman wrote: I know the club does not. I don't know of any members that have one.

Thanks!

Well excuuuse me.    Certainly you noticed, this is a marine aquarium club. You posted in the "Discussion" section where we talk about all things about marine aquariums. There is another section for non-aquarium stuff. It's labeled "Off Topic" 

Edited by Mark Peterson - May 17 2016 at 7:52am

When I stand back and take a broad look at an aquarium and compare it's general intensity of light with that of the lighting in the surrounding room, taking into account whether the light in the room is artificial or natural, sunny day or cloudy day, I can see differences and make rough evaluations of whether it's too much or not enough light for coral. Granted, I've seen 1000's and worked on many 100's of aquariums over the years, so I really shouldn't expect other hobbyists to see what I see. Unfortunately, I have not had enough experience with viewing LED intensity and as I will try to explain below, my eyes do not have the ability to do it.

Edited by Mark Peterson - May 17 2016 at 10:16am

The new Apogee MQ-500 does a lot better with LEDs and the harder to read ranges of deep reds. Check out Dr. Bugbee here talking about quantum sensors. I purchased the MQ-500 and am extremely happy with it.

IronMonkey wrote: The new Apogee MQ-500 does a lot better with LEDs and the harder to read ranges of deep reds. Check out Dr. Bugbee here talking about quantum sensors. I purchased the MQ-500 and am extremely happy with it. https://youtu.be/Pc_tqLYhITA Plus, I really like supporting a Utah company :-) -Adam

Apogee is local company? I'll definitely look at the video. Thanks for the response!

"When I stand back and take a broad look at an aquarium and compare it's general intensity of light with that of the lighting in the surrounding room, taking into account whether the light in the room is artificial or natural, sunny day or cloudy day, I can see differences and make rough evaluations of whether it's too much or not enough light for coral."

Maybe I'm missing the goal you're trying to portray by directly comparing ambient light to a captive reef aquarium's light source. How does this comparison help determine the amount of PAR over the reef?   When comparing light from a multiple bulb T5 fixture (assuming a mixture of different bulb types, number of bulbs, wattage, height over the water line, etc), a metal halide fixture (assuming different wattages, bulb types, number of bulbs, height over the water line, etc) and even a LED fixture where there could be any imaginable combination of intensity and spectrum, how can human eyes determine the amount of light, in this case PAR, being emitted from this vast selection and variations of these light sources? You even state; "Because our eyes generally register the full spectrum, they are just as inadequate as the meter. What looks to us as dim light is actually burning coral." So unless you mean that our eyes can see if corals are getting enough or not enough light based on our viewing of bleaching corals and therefor come to the conclusion there is in fact too much PAR over the reef, I find that claim to be very misleading, contradictory, and an uneducated statement. I find it impossible that one can just "eye ball it", as you've suggested, without the direct result being bleached corals.

"LED's don't emit a full spectrum."

I think that is a very regurgitated and dated response. There are so many different types of fixtures on the market today. So let's take the fixture I chose for example, the EcoTech Radion Gen 3 Pro. I chose it specifically because it does emit a full spectrum, 350nm to 750nm. It is my understanding is that that that is a a full spectrum. The graph you posted even suggests the very claim you were arguing against (a lot of those LEDs are in many popular fixtures on the market today.)

Mark Peterson wrote: Eyeballing it means to make a rough judgement, but never mind that. I'm just an old fool that was doing aquariums before you were born. I have a sense for this that few people understand. It's sad (and may I say chicken) that you would not call me but rather accuse me in public of being stupid. You have no idea how much I know and with no offense intended, I say that you don't know what you don't know.  In the graphs I posted above it's very plainly exhibited that individual LED's emit only a very tiny peak of energy in their intended spectrum. Even the white LED's do not give full intensity across the complete spectrum as emitted from the sun. If you cannot see that in those graphs then we have no where else to go with this discussion. Aloha, Mark Â

First of all Mark, I'm in no way trying to make you look stupid. However, I am arguing against your points you've made in a public reef aquarium forum regarding the discussion at hand for others to see two differing opinions on the subject. If you are threatened by that, maybe a healthy argument about something so specific in our hobby is not something you should engage in any longer.

I've never once resorted in calling you names or insulted your actions. I think this says more about you than it does about me. I believe I am being objective in this discussion, but it seems to me that you have been very unclear and contradictory with your statements, which I am merely trying to obtain clarification by asking specific questions.

Mark, please don't belittle or question my intellect again.

Evan

Found this (post below) on another site the other day. Thought it was interesting so I downloaded the LUX meter and what I found was pretty cool when I measured full sunlight, cloud cover and indoor light intensities.

Edited by LakeCityReefs - May 24 2016 at 8:51am