Watts Per Gal

[simonbrown403]

Reading this in menders pic area, just a quick question.

Lenna........ gf255- It's currently 2wpg as I have mainly low light plants, but I'm thinking of adding a little more so I can try some more demanding things.

gf225....... That's a nice amount of light in a large tank. I'd say that you will probably already be able to grow more demanding species. The Watts per Gallon "rule" becomes more lenient with larger volumes i.e. 2 WPG in a 180G is a lot higher intensity than 2 WPG in a 20G. Bearing in mind I grow Glossostigma elantinoides easily with only 2.1 WPG in my 33G I'd say you could grow more than you may imagine.

Why dose the Watts per Gallon "rule" becomes more lenient with larger volumes, why is 2wpg on a 180gal more intense than to 2wpg on a 22gal?

 

[Themuleous]

Hi,

I can't say I really understand this either myself but George gave me this link which explains it, if you can understand it that is!

http/rexgrigg.com/./mlt.htm

 

[George Farmer]

Hi,

I can't say I really understand this either myself but George gave me this link which explains it, if you can understand it that is!

http/rexgrigg.com/./mlt.htm

Exactly Themuleous, thanks.

There you go Simon.

 

[Themuleous]

George,

Any idea how to work out the Lux value of any given lighting system? I’m going to set up a nano tank and was going to work on the Rex's LSI value basis but I can't seem to find a simple explanation for converting the watt rating of my tubes to lux. Any ideas?

Sam

 

[simonbrown403]

Thank you all

 

[George Farmer]

George,

Any idea how to work out the Lux value of any given lighting system? I’m going to set up a nano tank and was going to work on the Rex's LSI value basis but I can't seem to find a simple explanation for converting the watt rating of my tubes to lux. Any ideas?

Sam

Sam

I assume that there's no fixed conversion formulae due to manufacturer's differences in tube specs/efficiency i.e. an 18W T8 Interpet Daylight Plus will have a different (higher) Lux rating of an 18W T8 Arcadia Original Tropical.

I realise that doesn't help in a practical sense but at least you know why you cannot simply convert Watts to Lux.

Interesting sounding project though, sounds like you're doing your homework at least!

 

[Themuleous]

George,

I’m trying! There is a LOT of info out there, but this forum is really helpful and interesting. It gives me something to occupy my mind with while at work lol

BTW do you have any recommendations for a plant that I can use to carpet the tank, was thinking glossa because it looks so good, but other suggestions would be welcome?

Simon,

No probs, not sure how much of a help I was, but keep me post on your progress, highs and lows, etc. I would be interested to know how you get on.

Sam

 

[Ptarmigan]

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[George Farmer]

do you have any recommendations for a plant that I can use to carpet the tank,

Where do you live?

For a small tank (and indeed large) I love Hemianthus callitrichoides (known as HC for short).

"This species of Hemianthus quickly forms a low, dense and brightly green carpet covering the bottom of the aquarium. Oxygen bubbles form on leaves resulting in vivid reflections of the light and in this way, a perfect foreground decoration is formed. Hemianthus callitrichoides may be planted directly into the substrate or attached to pieces of rocks and driftwood and it is suitable for large as well as small aquaria."

Unfortuantely it is very expensive in the US.

Look it up in the Tropica link in my signature for more info.

Here's it being used at its best (it's the moss-like carpet) - http/showcase.aquatic-gardeners.org/2004...ry=0&vol=3&id=8

* I dont think LSI is an SI unit of light is it ?

I think it's Candela.

To be honest I haven't read that link properly myself, I just knew it illustrated the WPG "rule change" in small tanks. I'll give it a go and get back to you.

 

[simonbrown403]

I knew about the minimum light thresh holed, but didnt realized it, the WPG rule didnt work with larger tanks.

The reason i asked is I'm planning a larger tank, and didnt want to be sticking huge amounts of light above it that will end up causing a massive algae invasion.

What would be the recommended wattage for a 6*2*2 foot tank for medium to high light.

 

[Lateral Line]

Anything involving an ich cannot be an SI unit, since an inch is not. I find the mixing of imperial, US and SI units in that article a little odd.

 

[Ptarmigan]

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[Themuleous]

George,

I live in Oxford. Ill see if I can get it mail order from somewhere, looks really good, Ill definitely give it a try. Looks like its very glow growing too, which would be better than the glossa in a tank that’s only 8in high! I’m guessing its light demanding though?!

All,

I guess what Rex's article was trying to illustrate (even if it is difficult to follow!) it’s that small tanks need comparatively more light that big tanks. I think that’s the simple answer here. So instead of going for 2WPG try 4, 5 or even 6. I also guess that every tank is different, if the plants grow, then they grow if not add more light!

Sam

 

[Ptarmigan]

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[Ptarmigan]

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