I bought the wrong bulb...

[FishFinatic77]

So, I went to my local hardware store and bought a florescent light bulb for my aquarium. (Yes, it was made for an aquarium.) Anyway, I got a 3400K bulb but it turned out to be a lot redder than I thought. I am going to replace it, but I can't get to the store right away so I wanted to know if the red light is okay for my fish.
Don't know if this is important but I have harlequin rasboras, cherry barbs, a honey gourami, and a clown pleco in the tank.
Thanks!

 

[Colin_T]

Just leave the bulb in the packet and take it back when you can. Get a globe with a 5500-6500K rating (K is for Kelvin). A globe with a 6500K is preferred because the Kelvin rating drops over time.

The red light you have now is fine for fish but the water will look more yellow and the fish won't show their colours as well as if the globe was 6500K.

 

[FishFinatic77]

Ok, thank you. I will definitely bring the bulb back because the light looks ugly. I'm going to leave the light in until I can replace it though, because I figure red light is better than no light at all.

Also, just out of curiousity, how would the red light affect my plants?

 

[Byron]

You did not mention if live plants are in this tank. They will need the light Colin suggested, but the smaller tubes (under 48 inches) in this K are generally too weak for plants. I can go into this more if you have plants.

The colour rendition of everything in the tank from fish to plants to décor will be natural under light with a 6500K rating.

 

[FishFinatic77]

I have anacharis, anubias, and some sort of plant with a long, single stem and round leaves. (I can't remember what it was called. Sorry!) What would the best light be for those plants, that would also be appropriate for the fish in my tank?

 

[Byron]

I have anacharis, anubias, and some sort of plant with a long, single stem and round leaves. (I can't remember what it was called. Sorry!) What would the best light be for those plants, that would also be appropriate for the fish in my tank?

With plants, the light Colin and I recommended is ideal. Plants need red and blue light to drive photosynthesis; green light improves their growth response even though it is not needed as far as photosynthesis. The tubes with 6500K are right on the mark as these are high in red, blue and green. This also produces a true colour rendition as I mentioned previously.

Next quesiton is, what is the length of the tube and what is the length/width/height of the tank? Light has to penetrate the water so this helps us work that out. The tube length is also important because once you are shorter than the 4-foot tube the manufacture of the tube is extremely important. Light intensity is not directly related to wattage, and a tube of say 24 inch length will have a wattage around 20w (varies depending upon manufacture from 17 to 20w). But within this one length you can find tubes much brighter than others, though the same wattage. This is because the phosphors and how the tube is manufactured can be very different. When I know the length of tubes I can specify those that will work for you. And I assume there is just one tube over the tank--or are there two in the fixture? And is it T8 or T5?

 

[FishFinatic77]

There is one bulb over the tank, and the bulb is an 18" T8 15W bulb. I don't know the exact dimensions on the tank, but it is just a standard 10 gallon. The manufacturer is aqueon.

 

[Byron]

There is one bulb over the tank, and the bulb is an 18" T8 15W bulb. I don't know the exact dimensions on the tank, but it is just a standard 10 gallon. The manufacturer is aqueon.

OK. There is one tube that will work here, the Life-Glo made by Hagen. Many fish stores carry this series, or you can get them online. You want the Life-Glo T8 18-inch. Here's a photo of the package, and they even include the spectrum chart showing the spikes in the blue, green and red. I only use this tube over all of the tanks with T8 less than 4-feet because it is the best for plants and it produces considerably more intensity than any other tube I have come across in T8.

 

[Fishmanic]

Zoo Med is another brand that makes a bulb that works well for plants

 

[Colin_T]

if you want more light, you can always get a twin light unit that holds 2 globes.

 

[FishFinatic77]

Ok, thanks everybody! I will look into where I can find those bulbs.

 

[Byron]

Zoo Med is another brand that makes a bulb that works well for plants

I was going to mention this tube, as it is my second choice over single tube tanks. I experimented a couple years back and found the Life-Glo a tad better over the same tank compared to the Zoomed Ultra Sun. But given the specifics here, primarily the smaller tank, either will do the job.

BTW, with dual tube T8 fixtures, a nice combo is one Zoomed Tropic Sun (which is 5500K so a tad "warmer" with more red) and one Life-Glo (or ZM Ultra Sun) at 6500K.

 

[Byron]

if you want more light, you can always get a twin light unit that holds 2 globes.

In NA this basically means making your own. T8 has been phased out primarily due to T5 (which ironically is too bright over most low-tech tanks) and then LED. I still use T8 because I understand it, having used it for three decades now. When my ballasts began to go, no new fixtures with T8 could be found locally or online, so I bought a shop dual tube unit and managed to get it in the housing of the old unit. If the manufacturers ever stop making the good T8 tubes, one will have no option but changing type.

 

[FishFinatic77]

Wow, I had no idea so much thought and consideration went into choosing lights! It makes sense though because you have to find light that replicates the habitat where the species of fish and plants you keep originally came from so they can thrive. Thanks everyone!