Uv causing cyano

[Barks]

Hi Randy.
I have a mature system and always run an oversized uv to stop ich.
I have battled with cyano for ages. Last year my ballast blew on the uv and aqua medic didn’t have any in the country. Within 2 weeks I lost my Koke tang and 2 other fish.
it was 3 months before I received the new ballast. During that time the cyano disappeared. I figured it just burnt itself out.
however 2 weeks after getting the new uv back online the cyano was back. I’ve tried everything. Setup a fuge for cheato massive water changes cleaning everything. No good.
it’s as if the uv is killing the only bacteria that out competes the cyano keeping it in check.
when the uv is off the cyano is gone after 2 weeks.
when it’s on its back after 2 weeks.
any experience of this or ideas
Regards
Barks

 

[CoralB]

Sorry for your loss ! But I’m interested in your observation regarding the UV causing cyano . Since the water going through the UV is only in the water column I wouldn’t think so but would like to hear other theories.

 

[Dan_P]

Hi Randy.
I have a mature system and always run an oversized uv to stop ich.
I have battled with cyano for ages. Last year my ballast blew on the uv and aqua medic didn’t have any in the country. Within 2 weeks I lost my Koke tang and 2 other fish.
it was 3 months before I received the new ballast. During that time the cyano disappeared. I figured it just burnt itself out.
however 2 weeks after getting the new uv back online the cyano was back. I’ve tried everything. Setup a fuge for cheato massive water changes cleaning everything. No good.
it’s as if the uv is killing the only bacteria that out competes the cyano keeping it in check.
when the uv is off the cyano is gone after 2 weeks.
when it’s on its back after 2 weeks.
any experience of this or ideas
Regards
Barks

Are you using a skimmer and GAC?

 

[vetteguy53081]

UV generally does not cause cyano but rather shock bacteria running through it. If bulb is expired or in need of replacement, may be inneffective allowing cyano to form.
What you can do for cyano manually is . . . . reduce white light intensity or even turn them off for 5-7 days. Add liquid bacteria daily for a week during the day at 1.5ml per 10 gallons. Add Hydrogen peroxide at night at 1ml per 10 gallons. Add a pouch of chemipure Elite which will balance phos and nitrate and keep them in check.

After the week, add a few snails such as cerith, margarita, astrea and nassarius plus 6-8 blue leg hermits to take control.

Some of the most common causes include:
- Protein skimmer which fills water with tiny air bubbles. As bubbles form from the reaction chamber, dissolved organic compound molecules stick to them. Foam forms at the surface of the water and is then transferred to a collection cup, where it rests as skimmate. When the protein skimmer does not output the best efficiency or you do not have the suitable protein skimmer to cover the tank, the air bubbles created by the skimmer might be insufficient. And this insufficiency of air bubbles can trigger the cyano to thrive.
- Overstocking / overfeeding, your aquarium with nutrients is often the culprit of a cyano bloom
- Adding live rock that isn’t completely cured which acts like a breeding ground for red slime algae
- If you don’t change your water with enough frequency, you’ll soon have a brightly colored red slime algae bloom. Regular water changes dilute nutrients that feed cyanobacteria and keeps your tank beautifully clear
- Using a water source with nitrates or phosphates is like rolling out the welcome mat for cyano. Tap water is an example
- Inadequate water flow, or movement, is a leading cause of cyano blooms. Slow moving water combined with excess dissolved nutrients is a recipe for pervasive red slime algae development

 

[Barks]

Hi all.
thanks for the detailed reply’s.
I have curve 7 in reefer 425xl works great.
I have new 5 stage ro.
I have 4 hydra 26hd with no red green and only 20% white.
I’ve started growing cheato to bring nitrates in balance with po so maybe.
the uv is 36w aquamedic helix turning tank once per hour for white spot works perfect new bulb recently.
it just caused the cyano when it came back online. Must be just a change in chemistry.
regards
Barks

 

[Tuna Melt]

I’m experiencing something similar. I just hooked up an oversized UV (40w for ~30 net gallons) to combat ich and suddenly red slime is coating things. Now my tank is super young and a lot has been changing quickly so It could be any number of thing but the timing of it coincides with the UV.

 

[Barks]

Hi. I figured the uv sterilised the cyano competition allowing it to take hold.
however your issue could be different. Uv is definatly a white spot prevention.
however my tank I think is too sterile and I’m now running it a bit dirtier.
this includes running the uv way faster so it isn’t sterilising but instead just exciting the bacteria with uv which may or may not increase the vitamin content of the bacteria which the sps may consume.
barks

 

[Randy Holmes-Farley]

There's not a lot of reports of folks getting cyano when using a UV, and I think coincidence is most likely, but the effect isn't impossible since a UV may kill off bacteria passing through it, and those degrading bacteria bodies will release organic matter that cyano can consume.

 

[TLO45]

I know this is an older thread that I just ran across but it seems I MAY be in a similar situation that I’m going to experiment with.
I have dealt with Cyano or similar issues (Dino’s perhaps) for at least a year. Trying to get ahead of the problem I installed a large UV unit. Although it is not set to an appropriate flow rate I have never been able to get rid of the Cyano even though I have tried a number of options.
Will run the system for a few weeks/months to see what happens.

 

[CoralB]

I know this is an older thread that I just ran across but it seems I MAY be in a similar situation that I’m going to experiment with.
I have dealt with Cyano or similar issues (Dino’s perhaps) for at least a year. Trying to get ahead of the problem I installed a large UV unit. Although it is not set to an appropriate flow rate I have never been able to get rid of the Cyano even though I have tried a number of options.
Will run the system for a few weeks/months to see what happens.

Just out compete cyano bacteria with a good bacteria like microbactor 7 or dr Tim’s .plus make sure your not zeroing out your nitrates and phosphates

 

[TLO45]

Just out compete cyano bacteria with a good bacteria like microbactor 7 or dr Tim’s .plus make sure your not zeroing out your nitrates and phosphates

I’ve tried that. No luck. However I did use dry rock which I will never use again if I do start again. True live rock is the key imo.
I’m sure my issues are bacteria based.

 

[CoralB]

I’ve tried that. No luck. However I did use dry rock which I will never use again if I do start again. True live rock is the key imo.
I’m sure my issues are bacteria based.

Cyano is a bacteria and by adding other good bacteria to out compete may take a little time . How long did you add good bacteria for ? Week , two weeks , month ?