Hiigh light or low, which am i :)

[Nick potts]

Hi all.

Well i have decided to give my tank a rescape and really concentrate on my plants, so first order of business is sorting out my lighting.

My tank is a 40cm cube of approx 55ltrs, and the current lighting consists of 1 18w 6500k power compact T5 and 1 15W PAR20 LED bulb, and also i use 15W PAR20 bulb with is all blue led's in the 420nm range, i use this bulb as i prefer the overall colour compared to the more yellow look with just the other bulbs.

So my question is where does that put me in the lighting realm, i have no must have plants at the moment apart from some DHG but don't want to be limited.

I will be using CO2 and EI

Thanks

 

[ceg4048]

See for yourself by reading the data on the charts provided in http://www.ukaps.org/forum/threads/help-device-needed.34811/#post-372453

Cheers,

 

[Nick potts]

Hmm interesting data but just looks confusing to me, and i have no way of accuratley measuring the par output of my bulbs

Just a general idea would be helpful

Thanks

 

[ian_m]

Just a general idea would be helpful

This is the issue with LED bulbs, every manufacturers LED bulb/fixture is different and different manufacturers products give greatly varying light outputs. So unless someone has access to exactly the same LED bulb as you and a light PAR meter, it is unfortunately like asking "How long is a piece of string".

I would suspect, as you have three light sources you will be in the medium to high region.

 

[ceg4048]

Hmm interesting data but just looks confusing to me, and i have no way of accuratley measuring the par output of my bulbs

Just a general idea would be helpful

Well it might be that you are misinterpreting the data on the charts because it tells you what the PAR values are.

Did you not specifically state that the tank is 40cm tall and that there is a PC mounted above it? If so then on the first chart it clearly shows the "Other PC" curve intersecting the 15 inch line at a PAR of about 40 micromoles. That's at the very edge of the low light zone just from the T5 alone/

As Ina points out you also have two additional fixtures which may drive you into the medium (pink) and possibly into the high (yellow) zone. If these are directional spotlights though it may not be an issue.

Cheers,

 

[Nick potts]

Thanks guys, and i understand the difficulty in judging lighting.

Just to get all info out, the lights are around 18" from the substrate and the LED's each have 5 x 3W cree bulbs, which are designed for coral growth and the beam is quite directional (which works in my planting style at the minute) and i do have fixtures in place to add another 2 led's.

 

[ceg4048]

Well again, according to the first chart the PAR is about 40 micromoles or so just from the PC which is perfect for tank startup. I don't see any need to do or to add anything else. If I were you I'd be much more worried about how CO2 diffusion and implementation will be accomplished because CO2 grows plants and light just makes them grow faster. CO2 is not just a button to be pressed or a valve to be opened. It's an art form that makes or breaks tanks every day. When flow/CO2/distribution are excellent then you can use however much light you want. When flow/CO2/distribution are marginal or poor then more light just destroys the tank faster.

Cheers,

 

[Nick potts]

Thanks your a very wise man

I believe i have very good flow and CO2 distribution in the tank, but always something to think about