Looking for old PAR data

[NormanB]

This may be a strange request, but hear me out.

I used to run 4 48" VHO bulbs over a standard 75g tank. 2 Super Actinic and 2 50/50 from URI.

I could keep and grow well anything I wanted from SPS to clams, and all LPS and softies I desired.

I now have a Reefbreeder V2+ 48 over a standard 75g tank.

I still don't think I'm putting as much light now as before, so I'm seeing if anyone has old PAR data on VHO bulbs over a similar depth tank.

TIA

 

[Rmckoy]

This may be a strange request, but hear me out.

I used to run 4 48" VHO bulbs over a standard 75g tank. 2 Super Actinic and 2 50/50 from URI.

I could keep and grow well anything I wanted from SPS to clams, and all LPS and softies I desired.

I now have a Reefbreeder V2+ 48 over a standard 75g tank.

I still don't think I'm putting as much light now as before, so I'm seeing if anyone has old PAR data on VHO bulbs over a similar depth tank.

TIA

Interesting …
I was in the same situation with the 8 bulb t5’s
actually I’ve had the same fixture for over 10 years . When it was over my 90 gal same as you said , there wasn’t anything I couldn’t keep or grow .
a tank filled with sps , lps, clams , anemones
But this current tank . Not so much luck

 

[mfinn]

Back before 2010 ( pre Radion days) I used mh lighting with VHO, and before that just VHO.
I honestly don't remember any talk about par numbers back then.
Those were the days of getting the most bulbs you could get over a tank and still be able to get into the top of the tank.

 

[NormanB]

Let me add a bit more information:

Bulbs were T12 110W each
So total wattage was 440W

That put the tank at 5.8 watts/gallon

Much talk at that time was watts per gallon...but I don't recall the recommendations any longer.

 

[NormanB]

This is from the LiveAquaria website: Still mentioning watts/gallon

A good basic rule to follow is to provide 1 to 2 watts of lighting per gallon for fish-only aquariums, 2 to 5 watts per gallon for freshwater planted aquariums, and 4 to 8 watts per gallon for reef aquariums. To calculate the number of watts per gallon an aquarium receives from a light fixture, simply divide the total wattage of the light fixture by the number of gallons of the aquarium. For example, a 55-watt fixture used over a 29-gallon aquarium will provide its inhabitants with slightly less than 2 watts of light per gallon. While this amount of light is perfect for fish-only aquariums, it may not be adequate for most photosynthetic reef inhabitants. Keep in mind that these lighting requirements will vary depending on the species you are keeping and the depth of your tank. It is essential to research the specific lighting requirements of each species.

 

[mfinn]

Yeah watts per gallon was the thing.
But that was back in the day where a good many people were trying to stuff as many 40 watt "reef" florescent tubes across their tanks.
Now a days with led lighting being such a dominate fixture in the hobby, par meters are pretty commonly used.

 

[NormanB]

I'll agree that PAR meters are used commonly, however the price is just nuts in my opinion. No aquarium store near me rents them and the online places are still a bit expensive.

I would still like to know what the older tubes did for our tanks.

 

[oreo54]

I'll agree that PAR meters are used commonly, however the price is just nuts in my opinion. No aquarium store near me rents them and the online places are still a bit expensive.

I would still like to know what the older tubes did for our tanks.

See this:
https://forums.reefcentral.com/threads/why-not-t12-vhos.193138/

Also believe Dana Riddle has data.

T12 ballasts we're expensive, low efficiency bulbs, and not energy compact enough.

Their "stand alone" life was probably very short

That T12 vho tubes held out on the merits of their spectrum and as supplements.

Watts/ par in vho apparently never matched or came close to t5ho.
Par measurements are always tricky since there was/ is reflector issues along with efficiency issues and how they were set up ( height ect.)


T12 vho " normal" lumens/watt was like 50.
About equiv. to the current worst LEDs
Not to mention inefficient delivery (restrike, reflectors, lenses ect)

Lumens as a subset of par gives some indication of the trend for the par numbers.

You had 460 watts of currently 1/2 the lumen efficiency of most LEDs,mh's, t8, t5,t5ho..... at the least.

There is no reason to believe ( with close to matching spectral compositions) par wouldn't follow this trend.


Point is it may be easier to use t5/ led data to extrapolate backwards to T12.

Also keep in mind " affordable" par meters " back in the day" had high errors in the blue spectrum so basically inaccurate for say a t12vho actinic tube.
Of course one can go into the " which spectrum is best" thing.

That said I'm sure some numbers are out there. If useable or not ???

https://www.reefaddicts.com/entry.php/228-Converting-a-T12-VHO-setup-to-T5-HO

Before we made the switch, we took a few readings. The daylight lamp in his T12-VHO setup was putting out 280 PAR at 6" from the sensor. The T12-VHO lamps all had internal reflectors.

By comparison, a comparable color temperature daylight T5-HO lamp with an external reflector was putting out 445 PAR!

 

[NormanB]

oreo, thank you for the links and your insight.

I believe I'm barking up the wrong tree on this and need to figure a way to inexpensively determine PAR for my current light.

The info may have been interesting, but fail to really "shed any light" hahaha on my thought process.

I still have at least 1 maybe 2 IC 440 ballasts stashed away, but have zero plans to use them. Along with them are VHO T12 endcaps and a brand new wire harness, too.

I suspect one day I'll need to room and they will end up in the landfill.

Thanks again for your time.

 

[Semisonyx]

Unfortunately you can’t really compare the two fixtures. With different spectrum, par comparisons don’t really provide any useful info. I used the same vho setup as you for years with great results. I can tell you having gone through it all with meters and measurements of different fixtures, you’ll use way less wattage (due to optics on your leds) than what you used for vho. Best thing you can do is use the par meter to set your fixture to an acceptable level of what you want to keep in your tank. It’ll probably look more dim to you than the vho setup, but trust the meter.

If you want to make use of your old ballasts, those 440s will drive 2 4’ t5 bulbs at a higher wattage, but you can still get about 9 months of life out of them with a fan. Flank your leds and use a couple of actinic bulbs to help get back the vho glow and hit some of the lower end spectrum that can be missing from the leds.

 

[NormanB]

Thanks for your thoughts.