"Need" high light for red plants? 1.8W/gal, see what you think

[Tom Barr]

Pretty red to me.........

24" or 60cm deep aquarium, and the lights are full 20 cm above the tank to boot. So the light at the bottom is about 50 micromols.

1.8 watts/gal of T5 lights

Works for my tanks and with ADA AS + EI modified style dosing(richer P).

Regards,
Tom Barr

 

[DaBub]

Before You Know It Folks will Break

I certainly agree that you need high light in the range of 1.5 to 1.9 watts a gallon to get those results.

 

[jonny_ftm]

Is this Altercanthera? If yes, than it is natively red, no?

 

[essabee]

Does this particular variety ever grow green?

 

[dutchy]

I don't have any problem to grow very red Alternathera at 1,35 WPG of T5, but a plant like Ludwiigia Repens only turns red in the top third part of a 24 inch deep tank.

 

[Brian20]

I think that depends about the light and plant. Not is the same a 1.8watts per gallon of t-5 that the same but whit t-12. T-5Ho have more lumens per watt.

 

[Philosophos]

It's not the big red alternanthera that's most telling, though that plant can look somewhat green at times. It's the very orange topped rotala in behind that really proves the point IMO.

 

[Tom Barr]

Normally red plants supposedly cannot grow except with "high" light.
Most of the issue is not being able to compare what old advice/myths mean by "high light".
So many think it means all watt/gal advice is correct for plants.

Most books and web sites still use this watt/gal range and few bother to see how little they can use and still get good results. They merely think, like many have in the past about low PO4, or algae etc, that because they saw some correlation, it must be right.

When someone else comes along and shows that they have been able grow it at 1/2 the light wattage, or with high N, P, etc.........they waffle and start looking for excuses. They rarely just go "oh well, I was wrong, let me see why I made this risky conclusion......."
Then see if it's true etc and even if they cannot manage it, they only have to look at multiple examples to realize maybe it's their own issue, not a general relationship.

People are very very "loose" with advice about light intensity and watt/gal, but very critical and specific with nutrients. CO2 is even worse, but it starts with lighting.

Hopefully this will change over time.
We started off good in the 1980's and 1990's, then after PC's came out, things started going sour.

Regards,
Tom Barr

 

[jeff5614]

I have 2x54 T5HO over a 75 and this is how my P stellatus looks. Dosing is standard EI for that size tank. It's not as red as Tom's pic above but the coloration is pretty good. Other aquarists occasionally ask the "secret" for the color but all I can answer is EI and maintaining good flow and CO2.

 

[jonny_ftm]

I have 2x54W at 12in height / 30cm + plexi cover on my 60gal. So, 1.8W/gal too, but 50% higher than Tom's setup. EI dosed + CO2 stable. No algae, very slow growth even on H. Polysperm and stellatus pruned every 3 weeks. But it is really green, a good green, no red or purple trace anywhere

With my actual low light, I also noted a dramatic change in Cryptocoryne Wendtii. It was a dark black-red-green with ondulated leaves under 4x54W at only 3in height (8cm). Now, with low light, only a dark red with more regular leafs aspect.

Limnophila sessiflora had gold yellow tops under high light, then turned into plain green

With EI and CO2, I find, in my case, the light to be a major impact factor on color. Maybe I need to lower luminaire with my actual 1.8W/gal for better color, but I hate pruning

 

[DaBub]

With & Without

Just a question have you tried without Plexiglas cover?

have read problems with covers altering effective light.

 

[jonny_ftm]

Just a question have you tried without Plexiglas cover?

have read problems with covers altering effective light.

No, because the growth speed suits me, plants are healthy (as Tom said, Red doesn't mean healthy) and I don't have to bother with cleaning my bulbs and reflectors since they are protected by the plexi cover. I could just lower my luminaire or plug in my two other 54W bulbs, but as I said, I hate pruning every week. Every 3-4 weeks is a real plus

 

[chris81]

Hi guys,

Amazing results. Light information is quite confusing and for a newbie like myself i must admit that conflicting views make matters much worsel Would 1.8 watts/gallon work for glosso too provided co2 and fertilisation are adequate?? I was planning on using 156 watts in my 180L aquarium but on reading this posts and others i just realised that with 4 watts per gallon im just waiting a time bomb to happen. My luminier consists of 4 x 39 watt tubes, now im confused as whether i use 2 or 3 tubes for 10 hrs a day or go on a time regimen where 2 tubes switch on for 2hrs than the 4 tubes switch on for 5 hrs than agaon to 2 tubes for the final 2 hrs. does this make any sens. WHich would be the best solution?? Thanks guys.. ALl this info is ofgreat help!

 

[aquabillpers]

"Watts per gallon" has been obsolescent for a long time, particularly since T5's and other high output bulbs have come on the scene. Maybe at some not too distant time bulb manufacturers will will start showing the micromoles (or lux for daylight bulbs) at a certain standard distance. That would bury WPG forever.

On another subject, I measured the effect that a clouded cover glass had on the the amount of light energy that got through it. It reduced the light by about 10 percent at 10 inches from the bulb.

Bill

 

[joyban]

Hi,

What is the Colour temprature of these lamps is it 6500K ? or more towards 4000K ?

Regards

Sujoy

 

[Tom Barr]

Gieseman daylight(3) and a 1 single Aquaflora

Regards,
Tom Barr

 

[joyban]

Is this POWERCHROME midday - a full spectrum lamp which closely imitates natural sunlight at 6000 Kelvin ? in T5 and POWERCHROME aquaflora in T5 ?

 

[shoggoth43]

Rather interesting development on that front....

http://www.amazon.com/dp/B001NP8N9G...e=asn&creative=380341&creativeASIN=B001NP8N9G

If that doesn't work, the important bit is in the title...

GE 73716 7-Watt Energy Smart PAR20 LED Light Bulb

While you can't see it, there's a listing on the front of the package for both PAR and Lumens. In this case 20 and 200 respectively. I didn't dig too far to find a distance at which is was measured though. Still, it's interesting to see that they are starting to include such information. My guess is that the information is already there for them for the LEDs but it may eventually end up on the other bulbs/lamps.

-
S

 

[jeff5614]

Is this POWERCHROME midday - a full spectrum lamp which closely imitates natural sunlight at 6000 Kelvin ? in T5 and POWERCHROME aquaflora in T5 ?

That is the combination I'm using.

 

[Tom Barr]

Is this POWERCHROME midday - a full spectrum lamp which closely imitates natural sunlight at 6000 Kelvin ? in T5 and POWERCHROME aquaflora in T5 ?

Yes.

Regards,
Tom Barr