I have a UV light (normally used for reptiles) over my one fry tank. Is it possible to get green water indoors from a UV light? The reason i ask is that the water in that tank has come to have a greenish hue even thougth it gets a 50% water change daily and has good params
I have a second tank set up the exact same just with a different light and it is clear.
I will try to post pics but I can't find batteries for my cammera at the moment.
Any experience or opinions would be appreciated
Thanks

It's a good finding if it is working in the other set up... what is your tank size. Light Specification, and number of fish? Do you follow regular 10x filteration rule in that tank? ( I just realize it is in your fry tank. )

You might want to try in your adult fish tank... Thank you..

It is about 25gal rubbermaid type container, I got rid of the package for the light bulb a long time ago when I first set up the light, it was not the strongest UV light it was originally for my birds but did not work well for their cage situation so I got a different one. Then when the fry showed up i needed a light and just grabbed this one. I would love to say with certainty that the filteration is 10x but these are the crappy filters that came with my bigger tanks so I am not sure how many GPH they do.

Now green water is supposed to be healthy for fish as far as I read, but is it okay for fry?

How big is your fry? Green water is good for adult fish but I am not 100% sure on fry though...

Can you post a pic please? Thanks.

as far as I've read (haven't had fry myself), green water is very beneficial for fry! I believe the closer to the sun's spectrum a light is, the more likely that you will get 'outside conditions' -promotion of green water. -I'd be interested to see if the fish under your UV light grows faster and stronger than the ones in the tub that isnt!

I have to get batteries for the camera tommorrow so I will post pics tomorrow.
As for the size difference I don't know if the two tanks would be objective as they were separated based on size already and the little ones are in the tank with out UV
Right now the fry are 6 1/2 weeks old and about 1" long

When I take a look at reptile's UV light at petsmart.com, it starts from 75 watts. Is it what you are using? or some lower wattages?

I would think the green water would be very good for fry...the free floating algea would mean they have a constant food source and should grow pretty quickly.

I can tell you it certainly is good for fry! I had two tanks in nice green and one not of the same spawning. I blew away the green with a UV before Tammy's visit - so she could see the fry she was picking. The fry in the green tanks had much larger numbers of deep bodied, solid babies - far fewer "weenies". They were larger, stronger and happier, I think.

The biggest problem was that it was nearly impossible to give a quick clean to the little "fry worms" (poos) thta gather in a tank each day. I could not see well enough to prevent a fry from going up the vacumn tube.

This is the type of light I have they can be found at PetSmart online


Daryl thank you for the reply I am glad your fry did well in the green tank

I got some pictures of the two tanks so they can be compared but the flash and light did not allow the color to show up great
Green tank


Clear tank



when I look at the tank the water seems to be the color of very thin pea soup
I hope it is green water and nothing else

It sounds like green water to me Thin pea soup is probably the best condition for them, I notice you can still see your fry easily through the water, which is good (less likely to siphon them out during water changes!)

I'm confused. I use a UV light to kill the algae and keep my tanks clear. Now we're saying it will promote algal growth. Is there a difference in the way a UV filter operates? Maybe the proximity to the light source?

The light from Super UV coil lamp produce UV-B which has 280 to 315 nanometers range.

The UV sterilizer is using UV-C (200 to 280 nanometers) and it will destroy the micro-organism.

Reference:
http://www.emperoraquatics.com/whatisuvsterilization.php

Does your green tank get any partial sun light? sorry for asking a lot of question..

Please don't be sorry for the questions I do not mind at all!!
I guess it might get some it is about 18 feet from the window and the venetian blinds are usually partially closed.
I am happy it seems to be green water cuz these guys will be going to and outdoor pond once they grow up a bit (and once I get the pond ) at least they will be used to it

Thanks for the reference Fred, that's great!