Need help on lighting...

[Jim Hollingsworth]

Hi Tom,

First question:

I want to use a slightly nonstandard setup and I am very unsure how much light to use.
I don't have access to a light meter and the units confuse me somewhat.
(How many millimoles per square inch per second are in a lux?, rhetorical)
I hope maybe you can help.

I want to use a low light, slow growth, easier maintainence setup.
I have a 75 gallon tank (48"x15"x24"deep).
I want plants growing out the top of the tank and therefore I want the
lights at 14" above the top of the tank.
I plan to use T05 HO 48" 54w 6500K fluorecent bulbs with reflectors.

I know there are a lot of variables, but given the tank depth, the light fixture height
and the low light setup plan, can you give me some idea of how many watts of T05 HO
would be good to use above this tank? (Or maybe help me with a plan to figure this out.)

I was thinking two 54 watt tubes for a total of 108 watts?
This is 1.4watt/gallon, but given the light fixture height and tank depth,
is this enough, maybe 3 or 4 tubes?

Possible emergent plants (also initial biomass)
Hygrophila corymbosa
Brazillian Penywort
Water Sprite
Bacopa caroliniana

Possible submerged plants
Tiger Red Lotus
Bolbitis heudelotii
Cryptocoryne wendtii
Java Fern
Java Moss


Second question, if I am allowed..

So how come you don't write a clear simple book with different levels of complexity
and examples of actual long term working tanks and make a bunch on money
and not work any more? (I think you could do it, there are a lot of people in
the world, you only need a very small percentage). It would also be useful and
bring enjoyment to people. However, who am I to say what you want.
Sounds like a neat project though. Maybe you have already
done or are doing it. If not I would help...

Thanks for your time... Jim

 

[Tom Barr]

Hi Tom,

First question:

I want to use a slightly nonstandard setup and I am very unsure how much light to use.
I don't have access to a light meter and the units confuse me somewhat.
(How many millimoles per square inch per second are in a lux?, rhetorical)
I hope maybe you can help.

I want to use a low light, slow growth, easier maintainence setup.

Okay, sounds good.

I have a 75 gallon tank (48"x15"x24"deep).
I want plants growing out the top of the tank and therefore I want the
lights at 14" above the top of the tank.
I plan to use T05 HO 48" 54w 6500K fluorecent bulbs with reflectors.
I know there are a lot of variables, but given the tank depth, the light fixture height
and the low light setup plan, can you give me some idea of how many watts of T05 HO
would be good to use above this tank? (Or maybe help me with a plan to figure this out.)
I was thinking two 54 watt tubes for a total of 108 watts?
This is 1.4watt/gallon, but given the light fixture height and tank depth,
is this enough, maybe 3 or 4 tubes?

You should be okay, I'd suggest perhaps a Tek 4x 54W light, then use only two of the bulbs, the only time you'd need more is for a few species of submersed plants maybe. Still, it is there if you ever change your mind(which you will).

With the 2 outside bulbs running, you get a nice wide spread and ample lighting. I do this on my non CO2 planted tank, submersed plants are few, and easy low light plants also.

Possible emergent plants (also initial biomass)
Hygrophila corymbosa
Brazillian Penywort
Water Sprite
Bacopa caroliniana

Possible submerged plants
Tiger Red Lotus
Bolbitis heudelotii
Cryptocoryne wendtii
Java Fern
Java Moss

These will all work well.

Second question, if I am allowed..
So how come you don't write a clear simple book with different levels of complexity
and examples of actual long term working tanks and make a bunch on money
and not work any more?

It takes a lot of work to produce a decent book I'd be happy with.
I have a dissertation to finish, that's a "book"
There's not much $$ in this hobby.
My area of research will yield a far better return than this hobby.
Aquariums are mostly done for the love of the hobby, not for $$.
Even the owners that do this hobby full time, are that way.

(I think you could do it, there are a lot of people in
the world, you only need a very small percentage). It would also be useful and
bring enjoyment to people. However, who am I to say what you want.
Sounds like a neat project though. Maybe you have already
done or are doing it. If not I would help...

Thanks for your time... Jim

I have a plan to get around to it, took me years to get around to having a web site with Greg.
I have many things on my plate like Greg, but we are both tenacious if nothing else.
That's is one trait I know applies to me.

Regards,
Tom Barr