Dsb's work, what makes them work best?
- Thread starter barryhc
- Start date
.TheFishMan65
New member
barry,
How are the phosphate pellets coming? How is your tank and have you learned anything new in the last 4 years?
How are the phosphate pellets coming? How is your tank and have you learned anything new in the last 4 years?
AtomHeart
New member
Wow, that was quite a read. What made me read this giant thread is the fact that I am one of the lucky ones that had a deep sandbed fail.
I was one of those beginners that started with a 4.5" RDSB in my refugium without really knowing much about it or its needed maintenance, etc. I have a 120 gal. DT, with a 45 Gallon sump. About half of the sump is partitioned off to be the refugium with DSB, red mangroves planted in it, and cheato floating above it, and it sets between the skimmer compartment (MSX-200 skimmer), and the return compartment that also runs chemical filtration (phosban, and carbon reactors). I originally cured my dead fiji rock in the tank with some live fiji rock for seeding, and did not add sand to the main tank until Nitrite was at 0 and Nitrates were down to 5mg/l. I then added a semi-shallow sandbed to the main display of varying depths from 2" - 4". Took it all very slowly, and didn't add inverts for 6 months or any fish for 8 months. Everything was a dream come true for the first year or so, but then things started declining.
First thing that happened was that my Cheato that floated above my refugium sandbed unexplainably died out one day. Since all my measurable parameters seemed fine, I left things as they laid, and didn't replace the cheato. Next thing I believe to be a contributing factor was both of my mexican turbo snails died, presumably from starvation. Since there was no algae in my tank at the time, I figured they starved, and since nitrates and phosphates measured at 0, I didn't want to put any back in for fear that they would starve.
Then, slowly at first, and then with frightening acceleration, my tank was overtaken with algae, and red cyanobacteria. For the longest time, I thought the red cyano was really just the dying algae, so didn't recognize with my inexperienced eyes that both problems existed. I thought it was just a cycle of some sort and would run its course, but it didn't...I continued with water changes...no help. Since I had only one fish in the tank, feeding was minimal, but my CUC was lacking, so I added some algae eating blennys. They weren't making a dent, and still my parameters for nitrate and phosphate were measuring 0. Tried upping my calcium and Carbonate Hardness and that helped some...the algae seemed to slow and stop growing. Added a batch of Mexican Turbo Snails and they helped a LOT, but just couldn't overcome the algae and cyano, so I started taking a long hard look at my neglected refugium and DSB.
When I looked at things down there, there was a ton of copepods, and bristleworms crawling all over...a reasonable amount of some unidentified ornamental macro-algae that was restricting most water flow near the sand surface, and about 1/2" of silt and detritus settled on the surface. It had never occured to me that DSB's required maintenance of any sort. I immediately tossed some small nassarius snails in from the main DT, hoping they would stir the sand a bit, eat some detritus, and get the system jumpstarted. Nitrates still being at 0, and phosphates still MEASURING at zero, I didn't feel much needed to happen. But then I noticed the black patch of hydrogen sulfide. Researched it and noted the rotten egg smell coming from the refugium.
Given the uncontrollable algae and cyano growth, as well as the hydrogen sulfide production, I considered this to be a "failed" deep sand bed, even if it was my own neglect that caused it to fail.
From this point, I isolated the refugium from the rest of the water column, then siphoned it out, along with the sand. Pulled out the red mangroves and put them in a bucket. Washed clean and dry the refugium section, then put back clean saltwater, and a fresh new ball of cheato.
I started the system back up at this point, and let it run. Over the next few days, the snails continued to battle the algae and cyano, my nitrates rose from 0 to 25mg/l. The cheato wasn't keeping up, and at this point, it is possible that my bacterial population would have ramped up to take on the extra load on its own, but I was too scared to wait and see. Doing 20 gallon water changes every other day, to battle the nitrates to keep all my fish and few corals safe, I purchased new oolitic sand, washed it several times, and installed it into the refugium to 4.5" depth. I then replanted my mangroves to help supplement the new cheato ball. This brought the nitrates down to 15mg/l. in one day. I then treated the tank with chemi-clean to kill the cyano. The cyano treatment ends tonight, with another 20 gallon water change, and I can then turn back on the skimmer, and put fresh phosban and carbon into the system via my reactors.
I consider this a disaster narrowly averted, but through it I realized how much denitrification my DSB was really doing. The semi-shallow sandbed in my main tank has me worried right now, and is probably the reason for the nitrates rising so quickly once the DSB was removed. At any rate, I need to pay closer attention to feeding, and how to get the right amount of food into the tank, so this thread has helped tremendously for someone like me who is only 1.5 years into this hobby.
I have ordered a refugium detrivore kit from Inland Aquatics, as well as 2lbs of microvert culture to seed the refugium with, and will go from there. I can now see places I've gone wrong, and places where I can do much better going forward to have a cleaner healthier looking tank. The algae and cyano is almost gone completely, and I am ready to start stocking corals once my nitrates are back to 0.
For now, everything is happy and healthy, and smells of fresh clean seawater. My Phosphate exportation going forward will be through:
1. Trimming cheatomorpha and removing trimmings
2. Phosban media changed out once per month
3. skimming heavily via MSX 200 skimmer
4. Siphoning of detritus during water changes
I was one of those beginners that started with a 4.5" RDSB in my refugium without really knowing much about it or its needed maintenance, etc. I have a 120 gal. DT, with a 45 Gallon sump. About half of the sump is partitioned off to be the refugium with DSB, red mangroves planted in it, and cheato floating above it, and it sets between the skimmer compartment (MSX-200 skimmer), and the return compartment that also runs chemical filtration (phosban, and carbon reactors). I originally cured my dead fiji rock in the tank with some live fiji rock for seeding, and did not add sand to the main tank until Nitrite was at 0 and Nitrates were down to 5mg/l. I then added a semi-shallow sandbed to the main display of varying depths from 2" - 4". Took it all very slowly, and didn't add inverts for 6 months or any fish for 8 months. Everything was a dream come true for the first year or so, but then things started declining.
First thing that happened was that my Cheato that floated above my refugium sandbed unexplainably died out one day. Since all my measurable parameters seemed fine, I left things as they laid, and didn't replace the cheato. Next thing I believe to be a contributing factor was both of my mexican turbo snails died, presumably from starvation. Since there was no algae in my tank at the time, I figured they starved, and since nitrates and phosphates measured at 0, I didn't want to put any back in for fear that they would starve.
Then, slowly at first, and then with frightening acceleration, my tank was overtaken with algae, and red cyanobacteria. For the longest time, I thought the red cyano was really just the dying algae, so didn't recognize with my inexperienced eyes that both problems existed. I thought it was just a cycle of some sort and would run its course, but it didn't...I continued with water changes...no help. Since I had only one fish in the tank, feeding was minimal, but my CUC was lacking, so I added some algae eating blennys. They weren't making a dent, and still my parameters for nitrate and phosphate were measuring 0. Tried upping my calcium and Carbonate Hardness and that helped some...the algae seemed to slow and stop growing. Added a batch of Mexican Turbo Snails and they helped a LOT, but just couldn't overcome the algae and cyano, so I started taking a long hard look at my neglected refugium and DSB.
When I looked at things down there, there was a ton of copepods, and bristleworms crawling all over...a reasonable amount of some unidentified ornamental macro-algae that was restricting most water flow near the sand surface, and about 1/2" of silt and detritus settled on the surface. It had never occured to me that DSB's required maintenance of any sort. I immediately tossed some small nassarius snails in from the main DT, hoping they would stir the sand a bit, eat some detritus, and get the system jumpstarted. Nitrates still being at 0, and phosphates still MEASURING at zero, I didn't feel much needed to happen. But then I noticed the black patch of hydrogen sulfide. Researched it and noted the rotten egg smell coming from the refugium.
Given the uncontrollable algae and cyano growth, as well as the hydrogen sulfide production, I considered this to be a "failed" deep sand bed, even if it was my own neglect that caused it to fail.
From this point, I isolated the refugium from the rest of the water column, then siphoned it out, along with the sand. Pulled out the red mangroves and put them in a bucket. Washed clean and dry the refugium section, then put back clean saltwater, and a fresh new ball of cheato.
I started the system back up at this point, and let it run. Over the next few days, the snails continued to battle the algae and cyano, my nitrates rose from 0 to 25mg/l. The cheato wasn't keeping up, and at this point, it is possible that my bacterial population would have ramped up to take on the extra load on its own, but I was too scared to wait and see. Doing 20 gallon water changes every other day, to battle the nitrates to keep all my fish and few corals safe, I purchased new oolitic sand, washed it several times, and installed it into the refugium to 4.5" depth. I then replanted my mangroves to help supplement the new cheato ball. This brought the nitrates down to 15mg/l. in one day. I then treated the tank with chemi-clean to kill the cyano. The cyano treatment ends tonight, with another 20 gallon water change, and I can then turn back on the skimmer, and put fresh phosban and carbon into the system via my reactors.
I consider this a disaster narrowly averted, but through it I realized how much denitrification my DSB was really doing. The semi-shallow sandbed in my main tank has me worried right now, and is probably the reason for the nitrates rising so quickly once the DSB was removed. At any rate, I need to pay closer attention to feeding, and how to get the right amount of food into the tank, so this thread has helped tremendously for someone like me who is only 1.5 years into this hobby.
I have ordered a refugium detrivore kit from Inland Aquatics, as well as 2lbs of microvert culture to seed the refugium with, and will go from there. I can now see places I've gone wrong, and places where I can do much better going forward to have a cleaner healthier looking tank. The algae and cyano is almost gone completely, and I am ready to start stocking corals once my nitrates are back to 0.
For now, everything is happy and healthy, and smells of fresh clean seawater. My Phosphate exportation going forward will be through:
1. Trimming cheatomorpha and removing trimmings
2. Phosban media changed out once per month
3. skimming heavily via MSX 200 skimmer
4. Siphoning of detritus during water changes
Last edited:
