watts VS. lumens
- Thread starter newbeestl
- Start date
Yes, however as a "general" thumbrule the wpg is more widely known and understood. The wpg thumbrule is going on a general "average" of lightbulbs on the market. I can really get into all the details, but thekrib has really covered this topic.
-Russ
-Russ
No. Lumens is a measure of the amount of light that we (humans) are able to see.
Watts is still a very general guide but for most uses it's acceptable imo.
Watts is still a very general guide but for most uses it's acceptable imo.
lumens is far more accurate, PPFD (par, pur) are even better. But they are singificantly more difficult (and expensive) to measure.
No, more lumens only mean that more of the output is in the range where the human eye is most sentitive, not necessarily in the areas which plants use, or which will give the best cotor redition for us. Example - typically 'Cool White" tubes have very high lumens per watt scores, but to my eyes a tank w/Cool Whites tubes looks somewhere between awful and dead. Yes plants will grow under, but if I can't stand to see the tank, what good does that do?
Triphosphor full spectrum tubes are likely to do better for your plants and may even look good to you.
Triphosphor full spectrum tubes are likely to do better for your plants and may even look good to you.
Newbeestl I don't know if you're familliar with this, but there is another rating on bulbs called K. K is the colour temperature of the bulb. I believe it is the temperature in Celsius a metal rod must be heated to look like that light bulb.
Often aquarists use this K rating as a basis for picking their bulbs, because like RTR mentioned, a big factor is how the tank looks to us. Usually we choose bulbs between 5000 and 10,000 K.
The Hagen bulbs are sort of misleading here. They have 18,000K ratings but still work well for plants and look pretty good in my opinion. The ones I'm talking about are aqua-glo and power-glo mostly.
Often aquarists use this K rating as a basis for picking their bulbs, because like RTR mentioned, a big factor is how the tank looks to us. Usually we choose bulbs between 5000 and 10,000 K.
The Hagen bulbs are sort of misleading here. They have 18,000K ratings but still work well for plants and look pretty good in my opinion. The ones I'm talking about are aqua-glo and power-glo mostly.
Captain Hook, I knew the 5 - 10k k range was good but didn't know why. Thanks for that information.
So lumens are what we see but may or may not be beneficial to the plants, and watts really don't have anything to do with light output but are a good general guide. :duh:
It sounds like the K rating is one of the bigger factors but most bulb packages don't list that.
Oh well, I'm looking at getting a new light hood that's compact fluorescent so I'll have plenty of light then, I'll just have to get in the 5 - 10 K range.
So lumens are what we see but may or may not be beneficial to the plants, and watts really don't have anything to do with light output but are a good general guide. :duh:
It sounds like the K rating is one of the bigger factors but most bulb packages don't list that.
Oh well, I'm looking at getting a new light hood that's compact fluorescent so I'll have plenty of light then, I'll just have to get in the 5 - 10 K range.
Don't get caught up with all the light lingo, most of them are misleading anyway (especially the k rating). The wpg rule of thumb is to keep things simple, you match that and you'll most likely provide optimum conditions for plant growth. That and what looks good to you should be all you need to focus on. What k rating bulbs look good for you? Best bet is to check them out for yourself because alot of them are rated arbitrarily like captain hook pointed out. The safe bet is to choose something that is labeled as full spectrum daylights, but you may find out you prefer something more white or even more yellow.
Over all, the best overall rating for a bulb for plants are 6,700K, or... i can never remember this, its 9,00o someting.. its not even anyways, but the later are very hard to find. The 6,700K's are fairly common (as far as compact flourecents go) and are very good for most plants.