6w/gal Light on 30min

[arty]

Hello,

One guy told me about growing plants on 6w/gal for 6-8 hr in day and lights going off every 30min for 30min
Fert. regime EI 30-35ppm Co2.

Some one tried before, this method works ?

Best Regards,

 

[bigmatt]

Sounds like a quick way to tons of algae to my inexperienced eyes! Must create a really unstable tank wih the light going on and off - you'll have to be bang on with your dosing. I'm sure one of the more knowledgable people will be able to advise more
Ceg4048 quotes Tom Barr's original EI experiments that calculated 6wpg to be considered "unlimited lighting" in his EI article, so i gues you could run a tank with this much light but it'd be hellishly hard work - massive dosing and daily water changes i'd guess!
cheers
Matt

 

[Fred Dulley]

Sounds ridiculous. Why on earth would someone want to do that.
I can imagine it now. "If I don't carry out this method, I get algae". Hhhmm maybe because you have 6WPG?!

 

[danmil3s]

i think in there you could run 6 wpg for 8 hours per day thats what EI is for unlimited lighting you would just need to build up to it slowly do %50 water change a week have you co2 spot on and Hugh amount of flow but unless you an expert and growing plants to sell why bother you'd be balancing on a knife edge and 6wpg of t5 would probably give your plants a tan

 

[Fred Dulley]

Since when has EI been for/been about unlimited lighting :?

 

[danmil3s]

its a long time since i reed it but im sure some where in the ei sticky its says 6wpg is maximum lighting and the EI mix is the fert level that worked under those conditions with that and you can go down to suit your needs but the base for ei is the most your plants will ever need because you cant drive them with more light its not fool prof but in toms test thats what he found but like i say i read it a long time ago

 

[Fred Dulley]

Maybe 2WPG but certainly not 6WPG. Not sure on the rest either..

 

[danmil3s]

ok sorry i cant find the info so maybe it was 2 wpg just thought the whole basis for EI was maxim ferts plants could use over a 7 day period before you "re set" the tank

 

[plantbrain]

EI worked at 5.5 watts per gal over a 20 Gal 45cm deep tank, or about 450 micromols.
Most weeds are around 400-600micromols of light saturation.

You get higher light use efficacy at lower ranges though.

My rational was if the light and CO2 are both non limiting, what nutrient demand would this equal? About 100% uptake vai EI. Since most folks use less than 450 micromols, EI should cover anyone from being limited. ADA AS and DIY Soil methods do this also, they just add all the ferts in the sediment, but the end result is similar. 6wpg is rather vague, it could be off by 300-400%, maybe more depending on which light set up you may have. Hence the use of a light PAR meter. I do not suggest folks use this much light, never have actually, more in the 2w/gal range for most, a little less for T5's even.

Regards,
Tom Barr

 

[plantbrain]

ok sorry i cant find the info so maybe it was 2 wpg just thought the whole basis for EI was maxim ferts plants could use over a 7 day period before you "re set" the tank

No, it was the higher end, 450 micromols, or about 5.5w/gal in that case.
Still, no need to go that high, which is why you can reduce EI without ill effects on many tanks with less light, which I also suggest if done slow and methodically.

Regards,
Tom Barr