UV sterilizing a breeding tank

[Yazu]

Is it possible to prevent egg fungus but using UV light? Does it harm the eggs or the fry?

 

[itiwhetu]

Egg fungus is only there, because the eggs are in fertile. If for example it is a batch of angel eggs, it is easy with a needle to pick off the infertile eggs. With egg scatters it is not such a problem. I do not advise using any chemical like methylene blue with eggs or fry.

 

[itiwhetu]

Didn't answer the question, simply don't know never played with UV light in a breeding situation

 

[Colin_T]

A ultra-violet (U/V) steriliser will reduce the number of disease organisms in the water. This includes things like protozoans, bacteria, viruses and fungus. However, it will only kill those organisms that pass through the U/V unit and are exposed to the U/V light. It will not prevent infertile eggs getting covered in fungus. The only way to stop fungus on eggs is to use something like Methylene Blue but most people don't bother and just have the eggs in clean water.

The light from a U/V steriliser does not harm fry or eggs in the aquarium and only kills things that pass through the actual U/V steriliser unit.

 

[mbsqw1d]

Depending on the setup, if this is an established heavily planted tank and the fry are pretty much free to fend for themselves by feeding on infusoria, then UV will destroy such organisms. IF of course as Colin says, they pass through the UV unit.