msderganc
New member
So I've been having an issue with cyano only on my sandbed only since June. I originally thought it was just the normal progression, but it has not gotten better. I don't see any other algae really at all, and I only clean my glass every ~5 days. I have no idea what to do, other than replace my sandbed at this point.
For some background on my tank, it's a 190g display, roughly 260g system. It's been up since November of last year. I'm currently using an ATI Powermodule 8x54w + 3x75w LED. The bulbs are about a month old (5xB+, 2xP+, and 1 C+). For filtration, I have a ~20g refugium with chaeto and live rock. I'm also running All-in-one biopellets, and ROX GAC in reactors, with Purigen passively in the sump. My skimmer is a SRO XP3000int. I'm running two Tunze 6105s and two MP40s for flow, in addition to about 1200gph through the sump.
In the tank, it's 90%+ SPS, with a few acans, zoas and palys. I have two small tangs, two schooling bannerfish, two watanabei angels, a foxface, and about 12 other smaller fish. I currently feed four cubes of homemade food per day (two in the morning, two in the evening), plus a small amount of Neptune Crossover Diet pellets twice a day in the middle. 3-4 times a week, I'll give them about a 3"x3" sheet of nori.
As for parameters, I've had some alkalinity swings recently, but I should be over them. I have a kalk reactor supplemented by dosers for calcium and alkalinity.
NO3 - .2 (Salifert)
PO4 - 0 (both by Hanna Phosphate and Phosphorus)
Alk - 7.5 (7.2-7.7)
Calc - 400
Mag - 1300
Salinity - 34ppt (slowly shifting up to 35ppt)
Here's what I've done so far:
1. Reduced feeding - seemed to have a negative effect, actually. I think it may have been due to less nitrate which stopped the bacteria from processing the phosphate.
2. Removed about half of the sand, going from a 1.5inch sandbed to about 0.75 inch - no change
3. Increased flow. I moved the MP40s to where they were pushing sand, essentially. This helped in some spots, but it more slowed the cyano than eliminated it.
4. 3 days lights out, 1 day actinics. Eliminated the cyano while the lights were out, then it came back like nothing had happened.
5. Vacuumed / stirred sandbed - seemed to get a lot of detritus up, but didn't effect the cyano. If I stir the sandbed up in the morning, it will stay clear until the next day.
6. Dosed bacteria / zeozym. I've tried every one of the products out there with no effect - zeozym, zeobac, coral snow, microbacter 7, prodibio, you name it.
7. GFO. I've been running various types of GFO, changing it as often as every couple of days thinking that it may be phosphates.
8. Biopellets. I've adjusted my effluent a number of times with no result. I've gone everywhere from a trickle to ~500gph. I've tried a few different types of biopellets as well.
9. Liquid carbon dosing. I have tried using NO3PO4X to reduce the nutrient levels while the biopellets were seeding. Extremely low nutrients, but little to no effect on the cyano.
10. Chemiclean. Finally, after all of that, I tried chemiclean. It worked well on the tiny amount of cyano on the rocks, but the sandbed was more or less unaffected. Maybe a slight recession, but not much. Twice now I've tried with no luck.
I know people are going to say it's a nutrient issue, but I'm not sure how that's possible. My phosphates are never over .05, and almost always read 0, even when the cyano has been removed. I don't have any nuisance algae growth except a relatively light covering of cyano on the sandbed (it's not smothering anything, looks more like reddish brown dusting on the sand). I'm pretty sure it's not dinos, since it doesn't bubble or go away at night.
I'm down to three possible solutions:
1. Replace the sandbed. Any suggestions? I was thinking Reef Flakes.
2. Try another chemical solution. Any suggestions?
3. Try removing the biopellets and just carbon dosing.
Any other recommendations? I'm open to anything at this point.
For some background on my tank, it's a 190g display, roughly 260g system. It's been up since November of last year. I'm currently using an ATI Powermodule 8x54w + 3x75w LED. The bulbs are about a month old (5xB+, 2xP+, and 1 C+). For filtration, I have a ~20g refugium with chaeto and live rock. I'm also running All-in-one biopellets, and ROX GAC in reactors, with Purigen passively in the sump. My skimmer is a SRO XP3000int. I'm running two Tunze 6105s and two MP40s for flow, in addition to about 1200gph through the sump.
In the tank, it's 90%+ SPS, with a few acans, zoas and palys. I have two small tangs, two schooling bannerfish, two watanabei angels, a foxface, and about 12 other smaller fish. I currently feed four cubes of homemade food per day (two in the morning, two in the evening), plus a small amount of Neptune Crossover Diet pellets twice a day in the middle. 3-4 times a week, I'll give them about a 3"x3" sheet of nori.
As for parameters, I've had some alkalinity swings recently, but I should be over them. I have a kalk reactor supplemented by dosers for calcium and alkalinity.
NO3 - .2 (Salifert)
PO4 - 0 (both by Hanna Phosphate and Phosphorus)
Alk - 7.5 (7.2-7.7)
Calc - 400
Mag - 1300
Salinity - 34ppt (slowly shifting up to 35ppt)
Here's what I've done so far:
1. Reduced feeding - seemed to have a negative effect, actually. I think it may have been due to less nitrate which stopped the bacteria from processing the phosphate.
2. Removed about half of the sand, going from a 1.5inch sandbed to about 0.75 inch - no change
3. Increased flow. I moved the MP40s to where they were pushing sand, essentially. This helped in some spots, but it more slowed the cyano than eliminated it.
4. 3 days lights out, 1 day actinics. Eliminated the cyano while the lights were out, then it came back like nothing had happened.
5. Vacuumed / stirred sandbed - seemed to get a lot of detritus up, but didn't effect the cyano. If I stir the sandbed up in the morning, it will stay clear until the next day.
6. Dosed bacteria / zeozym. I've tried every one of the products out there with no effect - zeozym, zeobac, coral snow, microbacter 7, prodibio, you name it.
7. GFO. I've been running various types of GFO, changing it as often as every couple of days thinking that it may be phosphates.
8. Biopellets. I've adjusted my effluent a number of times with no result. I've gone everywhere from a trickle to ~500gph. I've tried a few different types of biopellets as well.
9. Liquid carbon dosing. I have tried using NO3PO4X to reduce the nutrient levels while the biopellets were seeding. Extremely low nutrients, but little to no effect on the cyano.
10. Chemiclean. Finally, after all of that, I tried chemiclean. It worked well on the tiny amount of cyano on the rocks, but the sandbed was more or less unaffected. Maybe a slight recession, but not much. Twice now I've tried with no luck.
I know people are going to say it's a nutrient issue, but I'm not sure how that's possible. My phosphates are never over .05, and almost always read 0, even when the cyano has been removed. I don't have any nuisance algae growth except a relatively light covering of cyano on the sandbed (it's not smothering anything, looks more like reddish brown dusting on the sand). I'm pretty sure it's not dinos, since it doesn't bubble or go away at night.
I'm down to three possible solutions:
1. Replace the sandbed. Any suggestions? I was thinking Reef Flakes.
2. Try another chemical solution. Any suggestions?
3. Try removing the biopellets and just carbon dosing.
Any other recommendations? I'm open to anything at this point.
