swiss1939
Well-Known Member
I have started and stopped 2-3 reef tanks over the last 10 years. Always because I am moving, or trying to do it in a living situation that is not conducive to running a reef tank properly. Each time I feel like I learn from my mistakes and improve a bit. This was my last tank which was running ok until I went on vacation: https://www.reef2reef.com/threads/swiss1939s-second-reef-attempt-rsr-170.717921/ It crashed and then I moved during COVID so I paused on reef tanks for years again.
What I feel like I've learned from this second attempt is that while I was more patient than the first time, and I had all the equipment necessary to run the tank well, I was trying to intervene too much and wasn't letting the tank stabilize on its own before really intervening when necessary. I also was still not as patient as I should have been with stocking corals.
I have recently moved cross country to be near family, and finally gotten out of NYC. I again am in a sort of temporary housing situation as I am renting a house for a year, but plan on buying a permanent place after my lease is up here. So I am starting up the reef tank obsession again, but due to the temporary rental situation, I know that whatever tank I set up will have to come down again in a year. This leads me to using this year strategically by starting a smaller tank which I intend to allow to mature with only minimal fish in order to seed the rock and get the biological filtration and corraline algae started on my rock that I plan on using in the final tank build I'll start in the house that I buy next year.
This tank will be a FOWLR tank for this year, and since I will let it mature slowly over the next year, I took the chance to make my own oystercrete rock for the tank. I have been wanting to do that since the last tank build, but had to wait 5 years until I was in a better location to start up the hobby again.
I was originally planning on this FOWLR tank being built using a Mr. Aqua 22 gal long bookshelf tank, cause I love the widescreen format of low and long tanks, but this plan has changed by chance. I was looking at Petco's rip-off Mr. Aqua 22 gal long tanks because the Mr. Aqua tanks are out of stock everywhere. I know they don't stock those tanks in stores, only selling online, but I decided to take a trip to the local Petco just to look around at what tanks they had. While there, I noticed they were having a 50% sale on all open-glass tanks (through July 6, 2025). I don't particularly like old school plastic frame glass tanks like the cheap Imagitarium tanks they sell, but I couldn't resist considering them. One 20 gal long left, and a bunch of 40 and 60 gal breeder tanks. I was considering a 40 gal breeder for $75, but it just didn't feel right as I want to keep this tank size manageable while being big enough for a decent amount of rock to mature in it. I ended up saying screw it and buying the 20 gal long for $35, plus the metal tank stand that it fits on (which was not on sale) for $99. Total cost for tank and stand was $145. Half what just the Mr. Aqua 22 gal long low iron glass tank I was originally considering costs.
As a result, this boring FOWLR tank with a slow build pace is also becoming a low budget build!
I have made approx 75-100 lbs of oystercrete rock for a fraction of the price of the off the shelf dry rock.
Oystercrete rock materials used include:
Home Depot purchases:
94 lbs bag of portland cement - $13.88 - https://www.homedepot.com/p/94-lb-Portland-Cement-112494/100570364
40 lbs bag of morton water softener salt rock - $8.98 - https://www.homedepot.com/p/Morton-...Salt-Pellets-Clean-and-Protect-1500/100089553
8 qt bag of miracle grow perlite - $5.97 - https://www.homedepot.com/p/Miracle-Gro-8-qt-Perlite-Soil-74278430/204502291
2x50 lbs bags of Play Sand (used for casting the rock in plastic bins I already owned) - $9.74 - https://www.homedepot.com/p/Quikrete-50-lb-Premium-Play-Sand-111351/100318476
I didn't purchase the perlite specifically for this (had a bag lying around unused), and only used it for a few later pieces. I will always use it in the future.
Tractor Supply purchase:
50 lbs bag of Crushed Oyster Shells - $17.49 - https://www.tractorsupply.com/tsc/product/manna-pro-oyster-shell-50-lb
I have barely used any of the bag of cement and about 50%-70% of the bag of crushed oyster shells after making about 75-100 lbs of rock. I could make a crazy amount of rock with one or two more bags of oyster shells and perlite.
Total cost for this rock (which in the end will probably end up making about 150 lbs of rock just from the first bag of oyster shells and perlite): $56.06
The current running tally on this build is $201.06 for the tank, stand and rock.
Next step is to prep the rock in a plastic bin of freshwater to get rid of all the silicates and keep the pH from spiking in the tank. The rock will spend the next 6 weeks with a pond pump circulating freshwater through it all with weekly water changes (except for two weeks vacation in Ireland for the second half of June) in a plastic bin. Once the 6 weeks is up, I'll then rinse the same rock in the plastic bin with salt water for two weeks. Once that is done, then I'll fill the tank with salt water and sand and officially start the tank with rock in it.
The first bunch of rock was dried for about 4-5 days in the sun, and has been sitting in freshwater for about 5 days with 2 full water replacements. Still lots of silicates coming off the rocks. A few more rocks have been made and are drying in the sun waiting to join the rinse. I'll probably make a couple more batches of rock just to have more than enough with some variety sizes and shapes to choose from. Any rock that doesn't fit in this tank will end up cycling in a plastic bin in the garage, in which case I'll probably create a bunch more rock to fill that plastic bin and have plenty of seeded rock for my final tank build. Any unused seeded rock, once the final tank has been built, I'll trade or sell off next year.
My ultimate goal with this tank is to add life to the rock by dumping a bunch of copepod/isopod bottles and corraline algae seeding bottles into the tank, and let it exist with power heads for a few months to stabilize with a single fish in it for the first 6 months, then over the remaining 6 months slowly add a few other fish just to get the biological filtration to handle a larger biological load. I won't be concerned with algae, but am hoping that over the year any and all algae blooms will work themselves out and begin to stabilize by the time I'm ready to purchase a house.
It will be a very boring build with minimal updates, as this tank is really just a glorified rock seeding/curing barrel, instead of only doing it in a large plastic bin in my garage. This way I can at least have one fish to entertain myself.
What I feel like I've learned from this second attempt is that while I was more patient than the first time, and I had all the equipment necessary to run the tank well, I was trying to intervene too much and wasn't letting the tank stabilize on its own before really intervening when necessary. I also was still not as patient as I should have been with stocking corals.
I have recently moved cross country to be near family, and finally gotten out of NYC. I again am in a sort of temporary housing situation as I am renting a house for a year, but plan on buying a permanent place after my lease is up here. So I am starting up the reef tank obsession again, but due to the temporary rental situation, I know that whatever tank I set up will have to come down again in a year. This leads me to using this year strategically by starting a smaller tank which I intend to allow to mature with only minimal fish in order to seed the rock and get the biological filtration and corraline algae started on my rock that I plan on using in the final tank build I'll start in the house that I buy next year.
This tank will be a FOWLR tank for this year, and since I will let it mature slowly over the next year, I took the chance to make my own oystercrete rock for the tank. I have been wanting to do that since the last tank build, but had to wait 5 years until I was in a better location to start up the hobby again.
I was originally planning on this FOWLR tank being built using a Mr. Aqua 22 gal long bookshelf tank, cause I love the widescreen format of low and long tanks, but this plan has changed by chance. I was looking at Petco's rip-off Mr. Aqua 22 gal long tanks because the Mr. Aqua tanks are out of stock everywhere. I know they don't stock those tanks in stores, only selling online, but I decided to take a trip to the local Petco just to look around at what tanks they had. While there, I noticed they were having a 50% sale on all open-glass tanks (through July 6, 2025). I don't particularly like old school plastic frame glass tanks like the cheap Imagitarium tanks they sell, but I couldn't resist considering them. One 20 gal long left, and a bunch of 40 and 60 gal breeder tanks. I was considering a 40 gal breeder for $75, but it just didn't feel right as I want to keep this tank size manageable while being big enough for a decent amount of rock to mature in it. I ended up saying screw it and buying the 20 gal long for $35, plus the metal tank stand that it fits on (which was not on sale) for $99. Total cost for tank and stand was $145. Half what just the Mr. Aqua 22 gal long low iron glass tank I was originally considering costs.
As a result, this boring FOWLR tank with a slow build pace is also becoming a low budget build!
I have made approx 75-100 lbs of oystercrete rock for a fraction of the price of the off the shelf dry rock.
Oystercrete rock materials used include:
Home Depot purchases:
94 lbs bag of portland cement - $13.88 - https://www.homedepot.com/p/94-lb-Portland-Cement-112494/100570364
40 lbs bag of morton water softener salt rock - $8.98 - https://www.homedepot.com/p/Morton-...Salt-Pellets-Clean-and-Protect-1500/100089553
8 qt bag of miracle grow perlite - $5.97 - https://www.homedepot.com/p/Miracle-Gro-8-qt-Perlite-Soil-74278430/204502291
2x50 lbs bags of Play Sand (used for casting the rock in plastic bins I already owned) - $9.74 - https://www.homedepot.com/p/Quikrete-50-lb-Premium-Play-Sand-111351/100318476
I didn't purchase the perlite specifically for this (had a bag lying around unused), and only used it for a few later pieces. I will always use it in the future.
Tractor Supply purchase:
50 lbs bag of Crushed Oyster Shells - $17.49 - https://www.tractorsupply.com/tsc/product/manna-pro-oyster-shell-50-lb
I have barely used any of the bag of cement and about 50%-70% of the bag of crushed oyster shells after making about 75-100 lbs of rock. I could make a crazy amount of rock with one or two more bags of oyster shells and perlite.
Total cost for this rock (which in the end will probably end up making about 150 lbs of rock just from the first bag of oyster shells and perlite): $56.06
The current running tally on this build is $201.06 for the tank, stand and rock.
Next step is to prep the rock in a plastic bin of freshwater to get rid of all the silicates and keep the pH from spiking in the tank. The rock will spend the next 6 weeks with a pond pump circulating freshwater through it all with weekly water changes (except for two weeks vacation in Ireland for the second half of June) in a plastic bin. Once the 6 weeks is up, I'll then rinse the same rock in the plastic bin with salt water for two weeks. Once that is done, then I'll fill the tank with salt water and sand and officially start the tank with rock in it.
The first bunch of rock was dried for about 4-5 days in the sun, and has been sitting in freshwater for about 5 days with 2 full water replacements. Still lots of silicates coming off the rocks. A few more rocks have been made and are drying in the sun waiting to join the rinse. I'll probably make a couple more batches of rock just to have more than enough with some variety sizes and shapes to choose from. Any rock that doesn't fit in this tank will end up cycling in a plastic bin in the garage, in which case I'll probably create a bunch more rock to fill that plastic bin and have plenty of seeded rock for my final tank build. Any unused seeded rock, once the final tank has been built, I'll trade or sell off next year.
My ultimate goal with this tank is to add life to the rock by dumping a bunch of copepod/isopod bottles and corraline algae seeding bottles into the tank, and let it exist with power heads for a few months to stabilize with a single fish in it for the first 6 months, then over the remaining 6 months slowly add a few other fish just to get the biological filtration to handle a larger biological load. I won't be concerned with algae, but am hoping that over the year any and all algae blooms will work themselves out and begin to stabilize by the time I'm ready to purchase a house.
It will be a very boring build with minimal updates, as this tank is really just a glorified rock seeding/curing barrel, instead of only doing it in a large plastic bin in my garage. This way I can at least have one fish to entertain myself.
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