Can lighting enhance black in fish?

[Lusoluv]

I have a calico ranchu that had majority matte black coloring when I bought him (1st pic) and through quarantine. As soon as I put him in my main tank, with white sand, his black coloring looked brown. The main tank seeded the QT, and the parameters were the same at time of transfer. He is healthy, active, chubby and water parameters are still 0/0/10. I can't change the substrate, but wondering if my full spectrum LED light is washing him out? These are the specs on my Beamswork: 1700 lumen 25x 10000K, 6x Actinic, 3x Red, 2x Green.

Is there an LED light that would have a color spectrum that would make him look more black again? I have no plants to worry about. Thanks in advance!

 

[Andy Sager]

I have a calico ranchu that had majority matte black coloring when I bought him (1st pic) and through quarantine. As soon as I put him in my main tank, with white sand, his black coloring looked brown (pic 2). The main tank seeded the QT, and the parameters were the same at time of transfer. He is healthy, active, chubby and water parameters are still 0/0/10. I can't change the substrate, but wondering if my full spectrum LED light is washing him out? These are the specs on my Beamswork: 1700 lumen 25x 10000K, 6x Actinic, 3x Red, 2x Green.

Is there an LED light that would have a color spectrum that would make him look more black again? I have no plants to worry about. Thanks in advance!

A darker background will do more to enhance his black than the light colored sand will. Fish can change color to somewhat match their surroundings. You might try color enhancing foods but you are fighting a losing battle against a light background.

 

[Colin_T]

White and light coloured substrates will wash out the colours on most fishes including goldfish. If you add a bright white light to that, it will definitely cause the fish to stress.

The light unit you mentioned is more for marine tanks but can be used on freshwater. It has a lot of blue light and will make the water look clear and colours will be quite nice. However, bright white light reflects off the light gravel and the fish is suddenly in a brightly light place where its colour is causing it to stand out against the surrounding area. The fish compensates for this by trying to make itself lighter in colouration (it fades).

If you change the substrate to a brown or black, the fish will feel a lot more secure because it has a darker substrate and won't stand out against it.

A black, blue or dark green picture on the back of the tank will help improve the fish's colours too. You can buy aquarium backings from any pet shop or online. You can also make them from coloured card, newspaper or a plastic bin liner. Just tape it to the outside on the back of the tank.

Most LED light units can be programmed to have more or less of red, green, blue or white light. Many can also change the intensity of the light. If your light unit has this ability, you could turn off the actinic, and reduce the blue so it has the same amount as red, green and white light. If you can reduce the intensity, then drop that to 50% and see if it helps.

You mention no plants and that is another option. Floating plants will grow across the surface and shade the substrate reducing glare off the gravel and reducing the amount of light shining on the fish. Live aquatic plants will also be eaten by the goldfish and that is beneficial to the fish's health and digestion. Goldfish eat a lot of plant matter and should have plenty in their diet so they can remain healthy. If you don't want to have live plants, then offer the fish various green leafy vegetables, marine algae (available from Asian supermarkets), and vege pellets/ flakes.

 

[Lusoluv]

Thanks for your responses. My last tank had black background and Black Diamond sand. This time around I wanted to do something different. I took quite a while to find my heavy black calico, so imagine my disappointment after I moved him to my light tank! I have changed the pale gray background to navy. Changing or removing the substrate would obviously be challenging, let alone disruptive to water parameters. I ordered a Hygger LED that has more color options than my current one. I'll see if that makes a difference by dialing back the blue tones. The ranchu seems happy and bold, would love to get his bold coloring back!

 

[Andy Sager]

Just on a side note, if you ever take notice, most retail pet stores use a dark blue background because darker colors bring out the best colors in fish. White or light colors are great for silver colored fish but not much else.
As for changing out the substrate, if the bed doesn't get too deep, you can add a layer of dark substrate on top of the white sand instead of replacing all the existing sand. You could also use a large pore screening to separate the old and new substrates. Just use a screening that allows for water flow through it to prevent creating anaerobic pockets.

 

[Lusoluv]

I just ran a little experiment. Had some black ceramic tiles and laid them over the front half of my tank from left to right. My ranchu's color is almost black again. While I LOVE the look of white sand, I love my fish's colors more. I only have about 1" of white sand. How would I go about Googling/finding the right screening you're talking about Andy? This would definitely be do-able!

 

[Lusoluv]

I think without screening, my fish would mix the black and white sand as they're always combing through it!

 

[Colin_T]

If you have an established biological filter, you can replace the substrate without any real issues. Either change the substrate to a darker one, or add some floating plants to reduce the glare. My eyes hurt just looking at the picture with the white sand. I have eye lids, the fish don't.

If you don't have live plants, you don't need a light except to view the fish. If you have a coverglass on the tank, you could put some material on the cover beneath the light and it will filter the light. Just make sure the material is not in contact with the light because it could catch fire.

 

[Andy Sager]

I just ran a little experiment. Had some black ceramic tiles and laid them over the front half of my tank from left to right. My ranchu's color is almost black again. While I LOVE the look of white sand, I love my fish's colors more. I only have about 1" of white sand. How would I go about Googling/finding the right screening you're talking about Andy? This would definitely be do-able!

The screening I've used is usually used in porch screens and places like that. You do not want screen that is " bug proof" or "mosquito proof" as the holes would be too small.
That said, if you only have an inch of sand, you could actually just siphon off about 1/2 inch down then replace it with an inch or so of the dark substrate. At that point, even if there is mixing of the two colors, there should be more dark than light so it shouldn't matter. Between this and the lower light level, the fish's black coloring should darken up again.

 

[Lusoluv]

Well, I guess I have an project for the weekend!

 

[Andy Sager]

Well, I guess I have an project for the weekend!

 

[Lusoluv]

Well, changed the substrate to Black Diamond sand and voila - ranchu is back to black! Funny, my LED doesn't look nearly as bright as it did with the white sand, so no need to make any changes there.

Thanks for everyone's advice!

 

[Andy Sager]

Well, changed the substrate to Black Diamond sand and voila - ranchu is back to black! Funny, my LED doesn't look nearly as bright as it did with the white sand, so no need to make any changes there.

Thanks for everyone's advice!