Is this too much light?

[DiscusLoverJeff]

Hello friends,

I recently was given a 48" T5 - 4-54 watt bulb fixture. I want to know if I use it on my 95 gallon planted/discus tank if it would be too much light using 4 10k bulbs (thats what it came with and the bulbs are like new). The depth of my tank is 25" minus a 4" substrate of Eco-Complete.

I currently have a compact florescent light fixture using 4 - 65 watt bulbs now. I have 2 10k and 2 6500k bulbs. I feel I need more light for color of the discus and for the plants and was told that t5 is brighter and reflects over more space than CF. I am running co2 as well.

[Second Hand Pat]

I would give it a try since you already have the fixture. I read that the 10K bulbs are not great for plants. Will the fixture allow you to run three bulbs in case four are too many?

[DiscusLoverJeff]

Yes I can run one, two, three or all four. With the legs on it, it puts it about 24 inches off the substrate.

[Second Hand Pat]

Jeff, maybe replace two of the bulbs which are more plant friendly and you are good to go. Start with three and see how it goes. I'm suggesting three to see how it goes with algae (or not) growth.

[waters10]

This is a good link (http://www.plantedtank.net/forums/lighting/105774-par-vs-distance-t5-t12-pc.html) to get an idea of how much light you have. Just keep in mind that not all fixtures are the same and quality of reflectors and if they are individual, makes a difference.

Since you have CO2, you can go into hight light if you want.

Hope this helps.

[DiscusLoverJeff]

Thank you everyone very much. I will gradually make the transition over to T5 as suggested.

[greengreen84]

I would give it a try since you already have the fixture. I read that the 10K bulbs are not great for plants. Will the fixture allow you to run three bulbs in case four are too many?

sorry mate I have to disagree and agree with that one lol :) you will find that 5000k to 6500k is best to grow plants I will agree with that, but it won't penetraite the water that far so most people use it for the back of the aquarium to grow stems that grow tall near the surface, but at the frount of the light fixture you should have a 10,000k to penetraite the water as the blue spectrum in the 10,000k will allow it penetraite deeper in the tank so that way your foreground plants don't end up all raggy like and maybe die from lack of light depending on the plants requirements.

If you where going to do a tank with all 5000k to 6500k I would only recommend for 15 to and maybe 18 inch tall tanks depending on the fixture you have, so I strongly recommend you use 10,000k for your foreground plants growth as you have a very deep tank. As an example my tanks is all 10,000k because most of my plants are foreground plants and it's 18 inch tall

[Offpath]

sorry mate I have to disagree and agree with that one lol :) you will find that 5000k to 6500k is best to grow plants I will agree with that, but it won't penetraite the water that far

I actually tested this with a PAR meter when I setup my 210 gallon tank (29 inches high). I tested both 6500k and 10,000k bulbs both with and without water in the tank and found that (a) the water had minimal effect on the amount of light at the bottom of the tank, and (b) the effect was roughly equal for 6500k and 10,000k bulbs.

[greengreen84]

really thats just the general info I was taught when I first started? unless I was misinformed but if you have a par meter I won't argue that lol:), I would love to have a par meter just to test my lights to see when they need changing but can't convience myself to spend the money on it maybe down the track thanks for the info will look onto it more.

[ExReefer]

For reference, I have a 4 x 54W T5HO fixture on my 75G discus tank. I run just one midday Giesemann bulb from 5pm to midnight and keep anubias and crypts growing slowly. I have the fixture sitting directly on the tank rim without legs. It’s probably 1-1.5” from the water surface and the light has to shine through glass tops.

Two bulbs produced algae issues for my tank. Hope that helps.

[Offpath]

greengreen84, PAR meters are pretty expensive, given that you really only need to use them once. I borrowed mine from my local planted aquarium club--works much better when the cost is split by so many people. You might see if there's a planted aquarium club in Brisbane. I've also heard of aquarium stores that will rent them, too, though it seems to be a bit rare.