Lighting for Rimless Tank

[Hawkins409]

I am upgrading from a 75 gallon, traditional rectangular tank. The one I have is is 48" wide, about 18" deep and 20" tall (or so). I have T5 lights: I think 55w X 4. I am getting tired of this setup, and the tank is looking like it is about to start leaking on one of the seals, so I'm using this as an excuse to upgrade...

UPGRADE: I am going to switch to a rimless tank setup, and switch to a square tank. The one I am looking at is 93 gallons. 30" wide, 30" deep and 24" tall.

My question is about lights. What do I need to be looking at for lighting? The light I have is not only too wide, but evidently it is not the type that is made for a rimless tank (I am assuming because it would not handle the moisture from the evaporating water).

I don't mind if the light hangs from the ceiling above or if it suspends above the tank somehow.

 

[Brian_Nano12g]

What are your goals in terms of light level and co2 requirements? In other words, are you content with low tech or do you have ambitions for high tech? Reason I ask, a 24" tall tank gets a tad challenging to get full spectrum and high PAR to the substrate. Your lighting expenditures might may have to be liberal to achieve this.

BTW, who produces that huge rimless? Are you getting a high clarity tank (i.e. low iron / starphire glass )?

 

[Hawkins409]

I have pressurized CO2 now. My light level now is medium. 2.7 watts per
Gallon. I'd like to stay at least at a medium level of light. If that doesn't convert, I guess what I'm saying is that I would like to have about the same level that I have now or better.


Sent from my iPhone using Aquarium Advice

 

[Brian_Nano12g]

Have you looked at BuildmyLED.com? They have a calculator that you can plug in the light level and the tank. If the tank is unusual in dimension, you might be able to find another 24" tall tank to get an estimate on what you need. You can always contact them as well. They have options for spectrum and optics, in case you need more focused beam angle to penetrate taller tanks.

Or you can go with a t5ho system and suspend that. Look at TomBarr's tank for inspiration. Personally I prefer the LED route... but T5's sure can color up a tank nicely too. Lower initial upfront cost, but swapping bulbs annually can be a pain.

http://www.plantedtank.net/forums/showthread.php?t=485889

Edit: multiple ecoxotic e-Series fixtures may work as well.

 

[Brian_Nano12g]

I have pressurized CO2 now. My light level now is medium. 2.7 watts per
Gallon.

Also, watts per gallon is an irrelevant measure of intensity when it comes to T5HO or LED.

Have a read

http://www.plantedtank.net/forums/showthread.php?t=184368

 

[Hawkins409]

The reason to debunk watts per gallon are well explained. Still, there's not enough information there to tell how to calculate PAR for my aquarium or some hypothetical build. How does anyone figure that out without buying a PAR meter?


Sent from my iPhone using Aquarium Advice

 

[Fresh2o]

Here is a link from the TPT site with some graphs of PAR levels for various T5 fixtures. Scroll down a bit to get to the charts. http://www.plantedtank.net/forums/showthread.php?t=184368


Sent from my iPhone using Aquarium Advice

 

[Brian_Nano12g]

Either go with a company that takes those measurements for you and advertises them (ie. Finnex, Ecoxotic, BML, etc.) or use those charts and take a best stab at estimating it if you're going T5HO. Factors with T5HO mainly deal with reflector quality (polishing?), if the reflectors are over each blub and parabolic or a single reflector over multiple, bulb count, and distance from light to substrate. Also, some LFS's rent out a PAR meter. Some local planted tank clubs have them to share as well. Hoppy, the author of that article, builds and calibrates DIY PAR meters. I believe he sells them reasonably cheap. For me, I just go with LED companies and add the PAR values if I double up on fixtures.

 

[Hawkins409]

Fresh20, that's a link to the same article. I don't get how those charts will tell me how to determine my PAR value if I have a different bulb, different quantity of bulbs, etc. seems like there are way too many variables to base this on those charts. Is there a calculator? Or a more comprehensive set of charts? How do people really do this?


Sent from my iPhone using Aquarium Advice

 

[Brian_Nano12g]

Try the older version of that thread.

http://www.plantedtank.net/forums/showthread.php?t=105774

What t5ho fixture are you going to use? Reflector over each bulb?

 

[Fresh2o]

Fresh20, that's a link to the same article. I don't get how those charts will tell me how to determine my PAR value if I have a different bulb, different quantity of bulbs, etc. seems like there are way too many variables to base this on those charts. Is there a calculator? Or a more comprehensive set of charts? How do people really do this?


Sent from my iPhone using Aquarium Advice

Ha! No wonder it looked familiar. I would follow the link Brian posted.


Sent from my iPhone using Aquarium Advice

 

[Hawkins409]

To get familiar with how this is done and to set a baseline, I thought I'd try to calculate the PAR value for money current level light.

Nova Extreme. 4 x 54 w bulbs. 10,000, 10,000,
6,700, 5,000.

There is a single sheet of rippled reflective metal for the reflector which extends behind all four bulbs.

If say it is 22 inches above the substrate and 3-4 inches above the water.


Sent from my iPhone using Aquarium Advice

 

[Brian_Nano12g]

So, using this chart, and since a single sheet of rippled reflector is going to fall under poor to fair reflectors, at 22"... I see about 30 to 35 PAR from each bulb. 35x4 = 140 PAR is the estimate. Which is very high light.

 

[Hawkins409]

Brian, thank you for explaining that. It makes much more sense now.


Sent from my iPhone using Aquarium Advice