I am trying to find a natural nutrient balance in my tank and have been having a slowly recurring issue with cyanobacteria since the tank was started.
Tank Hardware:
- 40 Breeder, external overflow, 15 gal sump
- 2 MP10's running Reef crest, maxing at 40-ish percent
- 2 AI primes (mounted 12" above water line) on a 7am-8pm schedule. 8 hours of max intensity light (mostly blues/violets at 80%) Quick ramp up/down
- 2 Eheim 1250 Return pumps plumbed with 3/4" returns (4.5' head height), each plumbed to its own 1/2" RFG
- Mesh filter sock cleaned/changed weekly
- Slightly undersized skimmer (SCA-301) that is skimming on the dry side
- Red Gracillaria Fuge, lit with a kessil H80 (max intensity on the red grow setting) that is on from 8pm-7am (reverse of display photoperiod)
- Tunze 3155 ATO
- 5 Stage RODI system for ATO water
Fish/CUC Stocking List:
- 3.5" Yellow Corris Wrasse
- 2.5" Pink Fairy Wrasse
- 3" Juvenile Scopus Tang (plans already in place to rehome when it outgrows the system)
- 3" Scooter Blenny
- 2" Purple Firefish
- 1.5" Spotted Mandarin
- 1" Yasha Goby
- 1.25" Diameter Blue Tuxedo Urchin
- 2 Fire Shrimp
- 1 Skunk Cleaner Shrimp
- 2 Sexy Dancer Anemone Shrimp
- Dwarf Cerith, Trochus, and Nassarius Snails (Populations have levelled out to tank requirements)
- 1 Emerald Crab
- 1 Pitho Crab
- I know this is a heavily stocked 40, everything is doing well, is not stressed, is eating well, and can be rehomed to another tank when/if necessary
Coral Stocking:
- Primarily LPS and Soft Corals (working towards stability before trying SPS)
- 3 Hammers (15-20 heads combined)
- 2 Frogspawn (7-10 heads combined)
- 2 Torches (10-12 heads combined)
- 10-ish large mushrooms (Yuma, Ricordea, Discosomas)
- 20-ish Rock flower anemones
- Multiple Wellsi Blastos (10-15 head combined)
- 4" Diameter Pearl Bubble
- 2 1.5" Diameter Gonipora
- 2 1" Diameter Alevopora
- 100-150 heads of different types of Zoas
- 3" Diameter Plate
- 4" Square Colony of Favia
- Some other smaller coral additions that would be insignificant to nutrient levels
Other Tank Details to note:
- Tank has been running since April 1, 2020
- Substrate is 1" depth of Fiji Pink sand
- Tank was 'seeded' with Microbacter7 when setup
- Started with 30 lbs of dry rock, but has been seeded with another 10-15lbs from a clean and mature aquarium
- Coraline growth is great on rocks, but has slowed down in the past 12 months (not as much appearing on glass as it used to)
- Water changes have not been performed in 9 months (I moved over to automated dosing and cut water changes due to low nutrients)
- Tank is automatically dosed with All-For-Reef to maintain parameters
Feeding Schedule:
- 1/3 Cube of Frozen Mysis fed every other day (melted in tank water and all is added to display)
- 1/4 Cube of baby brine fed every other day (melted in tank water and all is added to display)
- Nyos Wild Goji Pellets (small amount fed every morning, only ever enough for fish to consume)
- Nori added to clip and fed every other day, opposite to the frozen food schedule. Most eaten, leftovers picked up by CUC
- Reef-Chili Spot Fed to select corals (Goni's, Alevopora's, Favia, Mushrooms) 2x weekly. Used to use Reef-Roids but it raised phosphates too much
Now onto the tank parameters and dosing. I moved to no-water changes and dosing in January of this year. I was initially dosing 5ml per day but I have had to cut back over the months due to what I believe is nutrient limitations, as my ALK and CAL were beginning to slowly rise. The tank is currently stabilized well with the All-For-Reef but has started to use less and less, currently dosing 1.7ml per day and maintaining the below parameters.
Parameters:
- Salinity: 1.026 (Refractometer checked with differing calibration fluids before each use)
- ALK: 9.5 dKh (Hanna Checker)
- CAL: 450 ppm (Salifert)
- MAG: 1400 ppm (Salifert)
- Nitrate: 2.5-5.0 ppm (Hanna HR)
- Phosphate: .06 ppm (Hanna Phosphorus ULR)
- PH: 8.15 (Salifert - Remains relatively constant throughout the day/night (8.0-8.2))
- Ammonia and Nitrite both are zero and have never spiked since the tank was cycled (Salifert)
Now onto the problem. Every 2 months the tank begins to get a bit dirty, but nitrate and phosphate levels remain constant. Nitrate bounces around in the 2.5-5.0 range and Phosphate stays at a consistent .06. I confirmed cyanobacteria under the microscope and have used chemiclean 3 times now (every 2.5 months) when the cyano begins to irritate zoas. The cyano is strictly on the rocks and in areas where flow is not an issue (not on the sandbed). I cannot blow it away with a baster, but it comes off very easily when touched (again this was confirmed cyano every time using samples from multiple areas of the tank under the scope). The chemiclean works great each time and clears the tank in 2 days, but I want to fix the root cause of the issue instead of band-aiding it with chemicals.
I believe that my low nitrate and high phosphate levels (traditionally non-balanced ratio) may be to blame. My plan is to begin dosing nitrate to get the level into the 15ppm range to see if balancing the nutrients aids in getting the tank to a desirable stability. I plan on beginning with Neonitro, just to see if the extra nitrate helps, before moving on to mixing my own solutions; dosing 1ppm a day until I get near the 15ppm range. I will also note that coral growth has been slowing down, all my corals are doing well with good color and PE, but they are not popping off heads as quick as they used to (LPS), and my zoas are not spreading nearly as quickly as they used to. The decrease in ALK consumption is also pointing me towards being nutrient limited as the uptake of ALK, MAG, and CAL has dwindled. I am also planning on getting an ICP test relatively soon just to see if anything else is amiss.
As this is my first tank and first time dealing with this issue, I just wanted to get some sort of checkup/confirmation from someone with more experience before I begin dosing Nitrate as a potential fix. Any and all help would be greatly appreciated and I can answer any questions if you have them. Thanks in advance!
Tank Hardware:
- 40 Breeder, external overflow, 15 gal sump
- 2 MP10's running Reef crest, maxing at 40-ish percent
- 2 AI primes (mounted 12" above water line) on a 7am-8pm schedule. 8 hours of max intensity light (mostly blues/violets at 80%) Quick ramp up/down
- 2 Eheim 1250 Return pumps plumbed with 3/4" returns (4.5' head height), each plumbed to its own 1/2" RFG
- Mesh filter sock cleaned/changed weekly
- Slightly undersized skimmer (SCA-301) that is skimming on the dry side
- Red Gracillaria Fuge, lit with a kessil H80 (max intensity on the red grow setting) that is on from 8pm-7am (reverse of display photoperiod)
- Tunze 3155 ATO
- 5 Stage RODI system for ATO water
Fish/CUC Stocking List:
- 3.5" Yellow Corris Wrasse
- 2.5" Pink Fairy Wrasse
- 3" Juvenile Scopus Tang (plans already in place to rehome when it outgrows the system)
- 3" Scooter Blenny
- 2" Purple Firefish
- 1.5" Spotted Mandarin
- 1" Yasha Goby
- 1.25" Diameter Blue Tuxedo Urchin
- 2 Fire Shrimp
- 1 Skunk Cleaner Shrimp
- 2 Sexy Dancer Anemone Shrimp
- Dwarf Cerith, Trochus, and Nassarius Snails (Populations have levelled out to tank requirements)
- 1 Emerald Crab
- 1 Pitho Crab
- I know this is a heavily stocked 40, everything is doing well, is not stressed, is eating well, and can be rehomed to another tank when/if necessary
Coral Stocking:
- Primarily LPS and Soft Corals (working towards stability before trying SPS)
- 3 Hammers (15-20 heads combined)
- 2 Frogspawn (7-10 heads combined)
- 2 Torches (10-12 heads combined)
- 10-ish large mushrooms (Yuma, Ricordea, Discosomas)
- 20-ish Rock flower anemones
- Multiple Wellsi Blastos (10-15 head combined)
- 4" Diameter Pearl Bubble
- 2 1.5" Diameter Gonipora
- 2 1" Diameter Alevopora
- 100-150 heads of different types of Zoas
- 3" Diameter Plate
- 4" Square Colony of Favia
- Some other smaller coral additions that would be insignificant to nutrient levels
Other Tank Details to note:
- Tank has been running since April 1, 2020
- Substrate is 1" depth of Fiji Pink sand
- Tank was 'seeded' with Microbacter7 when setup
- Started with 30 lbs of dry rock, but has been seeded with another 10-15lbs from a clean and mature aquarium
- Coraline growth is great on rocks, but has slowed down in the past 12 months (not as much appearing on glass as it used to)
- Water changes have not been performed in 9 months (I moved over to automated dosing and cut water changes due to low nutrients)
- Tank is automatically dosed with All-For-Reef to maintain parameters
Feeding Schedule:
- 1/3 Cube of Frozen Mysis fed every other day (melted in tank water and all is added to display)
- 1/4 Cube of baby brine fed every other day (melted in tank water and all is added to display)
- Nyos Wild Goji Pellets (small amount fed every morning, only ever enough for fish to consume)
- Nori added to clip and fed every other day, opposite to the frozen food schedule. Most eaten, leftovers picked up by CUC
- Reef-Chili Spot Fed to select corals (Goni's, Alevopora's, Favia, Mushrooms) 2x weekly. Used to use Reef-Roids but it raised phosphates too much
Now onto the tank parameters and dosing. I moved to no-water changes and dosing in January of this year. I was initially dosing 5ml per day but I have had to cut back over the months due to what I believe is nutrient limitations, as my ALK and CAL were beginning to slowly rise. The tank is currently stabilized well with the All-For-Reef but has started to use less and less, currently dosing 1.7ml per day and maintaining the below parameters.
Parameters:
- Salinity: 1.026 (Refractometer checked with differing calibration fluids before each use)
- ALK: 9.5 dKh (Hanna Checker)
- CAL: 450 ppm (Salifert)
- MAG: 1400 ppm (Salifert)
- Nitrate: 2.5-5.0 ppm (Hanna HR)
- Phosphate: .06 ppm (Hanna Phosphorus ULR)
- PH: 8.15 (Salifert - Remains relatively constant throughout the day/night (8.0-8.2))
- Ammonia and Nitrite both are zero and have never spiked since the tank was cycled (Salifert)
Now onto the problem. Every 2 months the tank begins to get a bit dirty, but nitrate and phosphate levels remain constant. Nitrate bounces around in the 2.5-5.0 range and Phosphate stays at a consistent .06. I confirmed cyanobacteria under the microscope and have used chemiclean 3 times now (every 2.5 months) when the cyano begins to irritate zoas. The cyano is strictly on the rocks and in areas where flow is not an issue (not on the sandbed). I cannot blow it away with a baster, but it comes off very easily when touched (again this was confirmed cyano every time using samples from multiple areas of the tank under the scope). The chemiclean works great each time and clears the tank in 2 days, but I want to fix the root cause of the issue instead of band-aiding it with chemicals.
I believe that my low nitrate and high phosphate levels (traditionally non-balanced ratio) may be to blame. My plan is to begin dosing nitrate to get the level into the 15ppm range to see if balancing the nutrients aids in getting the tank to a desirable stability. I plan on beginning with Neonitro, just to see if the extra nitrate helps, before moving on to mixing my own solutions; dosing 1ppm a day until I get near the 15ppm range. I will also note that coral growth has been slowing down, all my corals are doing well with good color and PE, but they are not popping off heads as quick as they used to (LPS), and my zoas are not spreading nearly as quickly as they used to. The decrease in ALK consumption is also pointing me towards being nutrient limited as the uptake of ALK, MAG, and CAL has dwindled. I am also planning on getting an ICP test relatively soon just to see if anything else is amiss.
As this is my first tank and first time dealing with this issue, I just wanted to get some sort of checkup/confirmation from someone with more experience before I begin dosing Nitrate as a potential fix. Any and all help would be greatly appreciated and I can answer any questions if you have them. Thanks in advance!
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