Great water quality, but big cyano troubles

[Polishpaul]

Hi long time lurker, first time poster. I've had my tank set up for 7 months now, slowly adding livestock and getting my filtration and flow just right.

I've had some algae outbreaks that were "typical" of a new tank, but now my refugium kicked into gear and is absorbing nitrates and phosphates really well. The API test barely detect them, and on the last electronic test at the LFS, I got 1 nitrates and phosphates under 0.1. Other water params:

150 gallon display with 25 gallon sump/refugium
Temp 78-80 (it's been very hot outside, heaters are set to 77 - I added a fan and trying to keep it under 79).
0 ammonia 0 nitrites.
Ph 8.0 alk 130 (currently dosing to slowly bring up).
Salinity 1.026
Calc and mg at the higher end of range.

I have 3x hydras 32, running them at 60% for about 6 hrs a day, and about 8 hours I run some dim UV/blue/moon light for enjoying my corals at night.

I think my feedings have been very sensible. I don't see food going to waste, what little gets missed by the fish gets swarmed by nassarius snails and hermit crabs.

So my issue is that now what looks like cyano is growing on sand (and almost exclusively on sand! Besides 2 small areas on the rock). I've physically removed 75% of it twice, dug some of the rest into the sand, but I am noticing it's increasing in intensity now with daily growth. Is this just a normal part of the cycle 7 months in?

Most of the advice online says "fix your water params" or "get better lighting". I can do more water changes (currently do 20% about every 3 weeks), but without much nitrates and phosphates is that really gonna help?

Anybody been stuck in a similar situation? Would love to hear your thoughts. I promise to come back later and update on my situation to help future reefers.

Thanks!

 

[lapin]

Cyano likes light and low flow.
It is perfectly normal to have cyano in your tank. Over time it should disappear as corals and other stuff uses up it nutrients and blocks its light.
Just keep on sucking it out.

 

[PeterC99]

Three things got rid of my cyano:

1) Strong UV light
2) Started an Oxydator (look for threads on this site)
3) Phytoplankton every other day

Before and after pics (also have since increased the light intensity by 10% on my Radions). I did not do anything to clean my sand.

 

[Polishpaul]

Three things got rid of my cyano:

1) Strong UV light
2) Started an Oxydator (look for threads on this site)
3) Phytoplankton every other day

Before and after pics (also have since increased the light intensity by 10% on my Radions). I did not do anything to clean my sand.

Wow awesome results. I'm running my flow at relatively low % of capability, but sand is almost kicked up in places and corals just barely tolerating it. I don't think I can do more flow without risking ripped tentacles.

I will up my UV light, and be more regular about feeding phyto. I never heard of an oxydator will look into that too and report back!

 

[PeterC99]

Good luck Paul!

 

[Biokabe]

One thing you can use - and I do not advocate using it here, not yet anyhow - is a product called Chemiclean. If what you have is in fact cyano (which it probably is, but there are a couple of other things that look similar to it), then Chemiclean will absolutely destroy it.

However, Chemiclean can be somewhat harsh on your tank, and you have to take some of your filtration offline while you're using it, so I personally don't recommend using it until it's really at plague levels (overgrowing corals in under a day). Better to use other, gentler methods first, especially because those other methods are just good reefkeeping habits that you want to develop anyhow.

 

[bg2311]

One thing you can use - and I do not advocate using it here, not yet anyhow - is a product called Chemiclean. If what you have is in fact cyano (which it probably is, but there are a couple of other things that look similar to it), then Chemiclean will absolutely destroy it.

However, Chemiclean can be somewhat harsh on your tank, and you have to take some of your filtration offline while you're using it, so I personally don't recommend using it until it's really at plague levels (overgrowing corals in under a day). Better to use other, gentler methods first, especially because those other methods are just good reefkeeping habits that you want to develop anyhow.

+1 on Chemiclean but can't stress enough to read and follow the instructions to the letter. You must increase aeration (we left our skimmer on and just turned the water level way down so it would not overflow or skim out the treatment). Can also point a powerhead at the surface to churn the water and increase gas exchange. Sometimes it requires more than 1 treatment but it does work well cyano.