Measuring PAR

Big Fate

IF measuring watts is a thing of the past how does one measure PAR? Before even a beginner had a simple method to go off of (wpg). But now that u add T5s HO, reflector angles and LEDs into the equation its a little more in depth to know where to begin.

So can someone please shed some light on this? How do you measure PAR?

Quantum

you measure PAR with a PAR meter, which will tell you the number of photons (between 400 and 700 nm wavelength) per square meter per second

Big Fate

So how do you know what to go off of if you dont own one? Like is there some sort of standard rule of principle anymore?

For example, if I just bought a 29 gallon tank, usually i would know I need 2 wpg atleast bare min to grow, how do I know which lights to buy anymore?

Quantum

Unless there is some reference that lists specific plants with their required PAR, knowing the PAR level would not seem to be very helpful. I suppose one could measure a the PAR level of a tank with proven results and then match that. But you could do the same not by quantifying the number of photons, but by using the same light fixture or at least using that to mark the starting point.

A 24" T8 fluorescent bulb can produce very good plant growth in a 29 gal, though higher light plants wouldn't do well. A T5HO bulb of similar size will be about 1.5 times the light.

Big Fate

What about a 18" T8 6,700 bulb in a 10 gal? (15 Watts)

Would that be sufficient to grow med-high plants if the Co2 and dosing is correct? If not, how much more light would I need to add to meet that demand by the plants?

Mikaila31

It would be good for medium plants IMO. But you could manage that tank without CO2 just fine. How much light you need depends on the plants you are trying to grow. There isn't a clear cut method, but using T8s to be in highlight with CO2 strongly recommend your usually looking at 3wpg+ . But it still depends on how well you can balance the tank and how efficient the fixtures are. IMO I would not bother with CO2 unless its pressurized, DIY yeast stuff I found to be more trouble then its worth. You also don't need CO2 you create a nice densely planted tank.

FYI few people own a PAR meter as they make pressurized CO2 look cheap .

Big Fate

Yea I have a 5 Lb Co2 tank with a JBJ regulator. Been wanting to fire this baby up for a while now, so I just got it refilled. Its true, I could get some good growth with no Co2 and the light i have.. But I want to grow Med-High lighting plants with fast thriving growth. I currently only dose Flourish Comp, but more than likely will grab a few dry ferts as well soon.

Thats why I was curious on what else I should add to my lighting to grow the higher end stuff since I'll be injecting Co2?

Mikaila31

Yes if you want to really do high light you will need a full dry fertilizer regime with daily dosing. I would suggest 2 T5 HO bulbs to get you into high light levels. FIY pressurized CO2 does not make things easy, I can guarantee you will have algae at first even with it and you will have to work to balance your fertilizers and CO2 to the light levels to get rid of that algae. High tech is just as much work, if not more then a well done low tech tank with good light on it.

I use CO2 and medium-high light tend to stick with low-medium light plants and just grow them really fast. Its hard to keep high light plants happy with lower light plants unless you are constantly pruning back their competition. I've grown some high-light plants before but with only weekly pruning they always get over run and smothered by the other plants.

Byron

This is sound advice, all of it, but the point about combining different-requirement plants is one not often considered and applies to any aquarium. Just as fish has differing needs, so do some plants.

On an unrelated note, Mikaila, I thought of you during my last trip to the Vancouver Aquarium. Their aquatic caecilians had bred, and they had five youngsters about 5-6 inches long in a mesh net to keep them apart from the parents (presumably). Did you ever breed yours?

Byron.

Mikaila31

No they never did, but I hope to someday. I was always hoping they would breed but last summer when I moved out I left my 55gallon at my parents for a month. I checked on it regularly, but I was called and told my female made her escape and after having her for 4 years that was the end of her. I still have my male and numerous requests to local shops to get more of these guys in. They are a PITA to find and my first pair was really just luck. Its been a year and I'm still looking =/ . I have some good shops locally but the main issue is that they rarely show up on wholesaler or exporter lists.