Hey All,
If you're reading this, welcome! I'm basically starting this thread as a way to document my own progression (all of the ups and downs) with building a Jellyfish Tank out of a slightly modified Fluval Flex 15. Admittedly I did get the idea from the Omni 8/9 which seems to be chronically out of stock so I decided to do it my own way. I initially thought I would save some money as well doing it this way, buuutttttt as I've learned with this hobby in the short time I've been trying to get into it, that is apparently not going to be as money-saving as I initially thought and hoped. I will say that so far, my experiment has been much cheaper than any of the common tanks of similar size available for purchase today and maybe this can be a starting point for others who are on a bit of a budget like me.
If you want to follow along, feel free. I'm happy to hear any input, advice, or criticisms you may have as I go along but I will preface this a little and say that I do not want to hear that Jellyfish cannot be in a tank with edges- we all know it and to be fair the concept has been proven false with the right modifications in mass produced tanks. If you are curious look up the Omni 8/9 by Jellyfish Warehouse, or the eon10 by Sunset Marine Lab.
I have done dozens of hours of research thus far learning about the basics of starting and keeping a saltwater tank, to the parameters needed by Jellyfish for this to be successful so I'm not just jumping into this blind, however I realize how much there is to learn and acknowledge I basically know enough to get myself in trouble ha ha. There is not a ton of information available online for Jellyfish keeping it seems, though I have found several good sources to help guide me and get me started in the right direction.
Now onto my build. I'm going to focus on what I specifically bought and put into my tank as well as what I bought to feed the Jellyfish and my slightly unorthodox stand. I think we all know that there are other basic supplies we need/keep outside of this and I won't go out of my way for those here. Since this is basically only going to be a Fish Only/FOWLR tank, I did select and use the API Saltwater Master Test Kit and added a Salifert Alk test kit a little later. With consistent water changes and the lack of any coral or similar organisms, I don't think I need to monitor any other parameters (though I'm open to hear if I'm wrong).
The goal is to create a unique tank to especially exhibit the Clownfish and Jellies I wish to add to it. Making it easy and stable are high on the priority list, hence the higher water volume for the tank, the use of a UV light, the addition of the hermit crabs to eat the scraps, and the sand to help make a better living area for the crabs and additional bacteria and trace elements.
Build:
-Fluval Flex 15 Gallon AIO
-Fluval 100 Watt heater
-Coralife Biocube 5 Watt UV sterilizer
-Sicce Syncra Silent 1.0
-An adjustable spray bar off of Etsy
-Small Shrimp-sized filter grates off of Etsy
-10 lbs of Aragalive Reef Sand
-StartSmart Complete
-Chemi-pure Blue
-Serra Siporax Mini Bio Media
-AquaVitro 8.4
-Tetra Whisper 20-40 Gallon Air Pump
-Plastic Mesh Sheets
-Brine Shrimp Hatchery Dish + Eggs
-Heavy Duty Metal Storage Shelves (400lb capacity per shelf)
-Aquarium Assistant App to help monitor it all and watch trends
Livestock (Current and Planned):
x4 Blue Legged Hermit Crab (Initially had 5, but one died within the first day I added. I firmly believe it was because my water was not oxygenating and I quickly added the air pump which seemed to save the rest of them as they were all looking poor.)
x1 Green Reef Chromis (currently in the tank to help what seems to be a totally stalled Nitrogen Cycle as I will explain later. Will rehome before Jellies are added)
x3 Jellyfish (I have bounced around a lot as to which ones I would like. More than likely Moon Jellies, but I have thoughts about different ones as well so I haven't fully decided. Either way, my tank will be designed to work for them)
x2 Clownfish (See Sunset Marine Lab keeping fish and Jellyfish together. I recently contacted them and was told this was a success on their end. I think I can replicate this as well.)
Mods:
The tank has some more... interesting... modifications, I think, in order to make everything I have planned for this project work. I will describe the best I can and include pictures when able.
-First, the addition of the UV light was problematic due to the tight space in the compartment. I had to take additional hose and create a sort of loop in the compartment to make it fit right. This hose actually proved to be beneficial for a DIY mod for heating my brine shrimp hatchery as well. It looks crazy, I'm sure it affects the flow rate coming out of the spray bar and probably adds some stress to the pump (which I have dialed down anyways so it isn't pumping anywhere near its max anyways), but it works well.
-Second, the etsy spray bar. It has an adjustable flow rate and each of the nozzles are adjustable to control where they spray to. It is a little shorter than I want and I'm not happy with how uneven the stream coming out of each nozzle is, but it is a quality part that I think may work for the Jellies.
-Third, the mesh netting. Before fully starting the cycle I ran a leak test and general test with tap water to mess with the tank and try out the spray bar. I noticed some slight dead zones near the rear and bottom of the tank (using tissues and paper towels to simulate a Jellyfish) and one or two of the "Jellies" getting caught on my bottom intake with the shrimp grate. I didn't want to take a chance so I bought some craft mesh and suction cups and added it to the back, creating curves in the mesh to keep Jellies away from those corners, my intakes, and to keep them closer to the current. It isn't as pretty as I would like, but it is fairly unobtrusive and looks fine enough. Plus, the Jellies being OK is more important
-Fourth, the sand layer. I used a relatively thin layer of AragAlive (about 1.5 inches or so) along the bottom of the tank. It is there purely for some bacteria, but mostly for the hermit crabs to be happy and for an easy place for food to settle and not be unsightly in the tank.
-Fifth, Brine Shrimp Hatchery. Especially now in the winter, I found my house too cool (in the 60s) for the recommended Brine Shrimp Hatching Temp. So I built a radiator inside the hatchery to help heat the water. The radiator runs from my return pump, pumping the aquarium water through the closed loop system and back into my return compartment heating the shrimp water without cross-contaminating or clogging. I have been able to get my hatchery water to read about 71 to 72 degrees in a room of about 66-68 which has been a mild success, though I was hoping for closer to the tank temp of 75.
-Sixth, a tank stand. I initially had some problems with a tank stand. I didn't like the one Fluval made (way too small and I wanted better storage options). The problem was money and the more unique shape of the Flex making it difficult to find something that would work. I made another post asking for help on a different stand, but ultimately decided it wasn't for me. I went ahead and purchased the steel shelfs to support my tank and can confidently say that it has now been about 10 days and everything seems to be working just right and shelf was perfect for me allowing both storage and not breaking the bank or my tank.
Starting:
I initially set up the tank and started the cycle on 1/22/23
-Day one was saltwater bought from my local aquarium shop. I checked the salinity and gave it a basic once over with API pH test. All parameters read fine and I added it to my tank on 1/21/23 along with the AragaLive sand and all of the filter media except the chemi pure. The UV light has also remained off as well. I allowed my heater to run for a day to get the tank up to 75 F. The next day I added the instructed amount of Start Smart Complete along with fish food and waited. I monitored the tank for about 4-5 days and never saw any increase in NH4+, NO2, NO3. Yup, they all read zero and StartSmart claims it would take one day to a week for the tank to cycle. This was after several mornings of adding fish flake food and even Baby Brine Shrimp from my hatchery at the beginning as well. I added another dose of StartSmart and gave it another day without results.
-On 1/27/23 I added the 5 mentioned Hermit Crabs in an attempt to help produce more NH4 and again monitored without any noticeable quantities of of NH4, NO2, or NO3. I only checked all 3 because I didn't know how the StartSmart may affect spikes and didn't want to miss one of them if it neutralized the NH4 and NO2 well. I did have a mild panic attack when I saw my pH plummet to 7.6 and even a little lower over the course of a day using my pH probe (even after calibrating) and I dosed using the 8.4 several times over the next few days but did not see any significant increase and my pH hovered around the 7.8-8.0 range. I stopped dosing after this and let it sit. Up to this point I had not done any dKh tests (and didn't even own a kit for it either). After another 3 days of nothing, I went to my local aquarium shop and got some advice/assistance. I had them check my water for me and we got the same results I had been getting. a pH of about 7.9 and no real noticable NH4, No2, or NO3. They gave me the Chromis to help with producing NH4 for the cycle and advised no more 8.4 as it could increase my dKh too much.
-I added the Chromis and began monitoring for NH4 only along with pH and I bought a dKh test to use as well. As of 1/29 I finally got a reading of .25 ppm for NH4! It was something and better than the straight 0 I was getting. pH still read low at about 7.8 in the morning. I was tempted to add more 8.4 but I held off. I just monitored the tank and fed as little as possible to help limit any massive bio dump using more brine shrimp and the occasional pellet food for the Chromis and Hermit Crabs. I also began dosing one capful of StartSmart to the main tank and a second directly over my filter sponge/media in the mornings after adding the Chromis.
- As of 1/31 I saw a bigger increase of Ammonia to 0.5ppm and it has held there as of 2/1 too. I'm optimistic this is the start for the cycle. I also did my first dKh test and it turns out I'm right at about 11 dKh which is much higher than I personally want and I'm aiming for about the 8 range. I need to figure out how to lower this.
Current Goals:
-I am not trying to chase numbers, but at a minimum, I will have to lower my temp a bit more to about 73 for the Jellies, I do need to lower my salinity from about 1.026 to about 1.023 or so, and I need a more consistent pH of about 8.1-8.2 which I just can't seem to be trending towards right now (despite the bubbler, open windows/doors, and added buffer). I am considering a large water change (30-50%) with a gravel clean to clean up any debris or problems in the sand, clear the high Alk a bit and maybe give better water for the cycle to continue in.
Future Plans:
-Install an ATO, install a skimmer, and install a mini refugium.
Some Encountered Problems:
-Difficulty in estimating if current spray bar is adequate for the flow I need in the aquarium, and whether it will damage jellies from its jets. Other thoughts and DIY have come to mind so I may modify at a later date.
-The Hermit crabs love climbing the netting to the top, and sometimes over, putting them into an area I don't want them in the main tank. I used to move them when I saw them. Now I'm seeing if any ever appear trapped. I actively saw one climb back over from the other side with little difficulty so this may not be as dire as I initially thought.
-Brine Shrimp Hatchery still running a little cool for my liking.
-May not have needed to upgrade my return pump, but time will tell.
Photos to come when I can.
If you're reading this, welcome! I'm basically starting this thread as a way to document my own progression (all of the ups and downs) with building a Jellyfish Tank out of a slightly modified Fluval Flex 15. Admittedly I did get the idea from the Omni 8/9 which seems to be chronically out of stock so I decided to do it my own way. I initially thought I would save some money as well doing it this way, buuutttttt as I've learned with this hobby in the short time I've been trying to get into it, that is apparently not going to be as money-saving as I initially thought and hoped. I will say that so far, my experiment has been much cheaper than any of the common tanks of similar size available for purchase today and maybe this can be a starting point for others who are on a bit of a budget like me.
If you want to follow along, feel free. I'm happy to hear any input, advice, or criticisms you may have as I go along but I will preface this a little and say that I do not want to hear that Jellyfish cannot be in a tank with edges- we all know it and to be fair the concept has been proven false with the right modifications in mass produced tanks. If you are curious look up the Omni 8/9 by Jellyfish Warehouse, or the eon10 by Sunset Marine Lab.
I have done dozens of hours of research thus far learning about the basics of starting and keeping a saltwater tank, to the parameters needed by Jellyfish for this to be successful so I'm not just jumping into this blind, however I realize how much there is to learn and acknowledge I basically know enough to get myself in trouble ha ha. There is not a ton of information available online for Jellyfish keeping it seems, though I have found several good sources to help guide me and get me started in the right direction.
Now onto my build. I'm going to focus on what I specifically bought and put into my tank as well as what I bought to feed the Jellyfish and my slightly unorthodox stand. I think we all know that there are other basic supplies we need/keep outside of this and I won't go out of my way for those here. Since this is basically only going to be a Fish Only/FOWLR tank, I did select and use the API Saltwater Master Test Kit and added a Salifert Alk test kit a little later. With consistent water changes and the lack of any coral or similar organisms, I don't think I need to monitor any other parameters (though I'm open to hear if I'm wrong).
The goal is to create a unique tank to especially exhibit the Clownfish and Jellies I wish to add to it. Making it easy and stable are high on the priority list, hence the higher water volume for the tank, the use of a UV light, the addition of the hermit crabs to eat the scraps, and the sand to help make a better living area for the crabs and additional bacteria and trace elements.
Build:
-Fluval Flex 15 Gallon AIO
-Fluval 100 Watt heater
-Coralife Biocube 5 Watt UV sterilizer
-Sicce Syncra Silent 1.0
-An adjustable spray bar off of Etsy
-Small Shrimp-sized filter grates off of Etsy
-10 lbs of Aragalive Reef Sand
-StartSmart Complete
-Chemi-pure Blue
-Serra Siporax Mini Bio Media
-AquaVitro 8.4
-Tetra Whisper 20-40 Gallon Air Pump
-Plastic Mesh Sheets
-Brine Shrimp Hatchery Dish + Eggs
-Heavy Duty Metal Storage Shelves (400lb capacity per shelf)
-Aquarium Assistant App to help monitor it all and watch trends
Livestock (Current and Planned):
x4 Blue Legged Hermit Crab (Initially had 5, but one died within the first day I added. I firmly believe it was because my water was not oxygenating and I quickly added the air pump which seemed to save the rest of them as they were all looking poor.)
x1 Green Reef Chromis (currently in the tank to help what seems to be a totally stalled Nitrogen Cycle as I will explain later. Will rehome before Jellies are added)
x3 Jellyfish (I have bounced around a lot as to which ones I would like. More than likely Moon Jellies, but I have thoughts about different ones as well so I haven't fully decided. Either way, my tank will be designed to work for them)
x2 Clownfish (See Sunset Marine Lab keeping fish and Jellyfish together. I recently contacted them and was told this was a success on their end. I think I can replicate this as well.)
Mods:
The tank has some more... interesting... modifications, I think, in order to make everything I have planned for this project work. I will describe the best I can and include pictures when able.
-First, the addition of the UV light was problematic due to the tight space in the compartment. I had to take additional hose and create a sort of loop in the compartment to make it fit right. This hose actually proved to be beneficial for a DIY mod for heating my brine shrimp hatchery as well. It looks crazy, I'm sure it affects the flow rate coming out of the spray bar and probably adds some stress to the pump (which I have dialed down anyways so it isn't pumping anywhere near its max anyways), but it works well.
-Second, the etsy spray bar. It has an adjustable flow rate and each of the nozzles are adjustable to control where they spray to. It is a little shorter than I want and I'm not happy with how uneven the stream coming out of each nozzle is, but it is a quality part that I think may work for the Jellies.
-Third, the mesh netting. Before fully starting the cycle I ran a leak test and general test with tap water to mess with the tank and try out the spray bar. I noticed some slight dead zones near the rear and bottom of the tank (using tissues and paper towels to simulate a Jellyfish) and one or two of the "Jellies" getting caught on my bottom intake with the shrimp grate. I didn't want to take a chance so I bought some craft mesh and suction cups and added it to the back, creating curves in the mesh to keep Jellies away from those corners, my intakes, and to keep them closer to the current. It isn't as pretty as I would like, but it is fairly unobtrusive and looks fine enough. Plus, the Jellies being OK is more important
-Fourth, the sand layer. I used a relatively thin layer of AragAlive (about 1.5 inches or so) along the bottom of the tank. It is there purely for some bacteria, but mostly for the hermit crabs to be happy and for an easy place for food to settle and not be unsightly in the tank.
-Fifth, Brine Shrimp Hatchery. Especially now in the winter, I found my house too cool (in the 60s) for the recommended Brine Shrimp Hatching Temp. So I built a radiator inside the hatchery to help heat the water. The radiator runs from my return pump, pumping the aquarium water through the closed loop system and back into my return compartment heating the shrimp water without cross-contaminating or clogging. I have been able to get my hatchery water to read about 71 to 72 degrees in a room of about 66-68 which has been a mild success, though I was hoping for closer to the tank temp of 75.
-Sixth, a tank stand. I initially had some problems with a tank stand. I didn't like the one Fluval made (way too small and I wanted better storage options). The problem was money and the more unique shape of the Flex making it difficult to find something that would work. I made another post asking for help on a different stand, but ultimately decided it wasn't for me. I went ahead and purchased the steel shelfs to support my tank and can confidently say that it has now been about 10 days and everything seems to be working just right and shelf was perfect for me allowing both storage and not breaking the bank or my tank.
Starting:
I initially set up the tank and started the cycle on 1/22/23
-Day one was saltwater bought from my local aquarium shop. I checked the salinity and gave it a basic once over with API pH test. All parameters read fine and I added it to my tank on 1/21/23 along with the AragaLive sand and all of the filter media except the chemi pure. The UV light has also remained off as well. I allowed my heater to run for a day to get the tank up to 75 F. The next day I added the instructed amount of Start Smart Complete along with fish food and waited. I monitored the tank for about 4-5 days and never saw any increase in NH4+, NO2, NO3. Yup, they all read zero and StartSmart claims it would take one day to a week for the tank to cycle. This was after several mornings of adding fish flake food and even Baby Brine Shrimp from my hatchery at the beginning as well. I added another dose of StartSmart and gave it another day without results.
-On 1/27/23 I added the 5 mentioned Hermit Crabs in an attempt to help produce more NH4 and again monitored without any noticeable quantities of of NH4, NO2, or NO3. I only checked all 3 because I didn't know how the StartSmart may affect spikes and didn't want to miss one of them if it neutralized the NH4 and NO2 well. I did have a mild panic attack when I saw my pH plummet to 7.6 and even a little lower over the course of a day using my pH probe (even after calibrating) and I dosed using the 8.4 several times over the next few days but did not see any significant increase and my pH hovered around the 7.8-8.0 range. I stopped dosing after this and let it sit. Up to this point I had not done any dKh tests (and didn't even own a kit for it either). After another 3 days of nothing, I went to my local aquarium shop and got some advice/assistance. I had them check my water for me and we got the same results I had been getting. a pH of about 7.9 and no real noticable NH4, No2, or NO3. They gave me the Chromis to help with producing NH4 for the cycle and advised no more 8.4 as it could increase my dKh too much.
-I added the Chromis and began monitoring for NH4 only along with pH and I bought a dKh test to use as well. As of 1/29 I finally got a reading of .25 ppm for NH4! It was something and better than the straight 0 I was getting. pH still read low at about 7.8 in the morning. I was tempted to add more 8.4 but I held off. I just monitored the tank and fed as little as possible to help limit any massive bio dump using more brine shrimp and the occasional pellet food for the Chromis and Hermit Crabs. I also began dosing one capful of StartSmart to the main tank and a second directly over my filter sponge/media in the mornings after adding the Chromis.
- As of 1/31 I saw a bigger increase of Ammonia to 0.5ppm and it has held there as of 2/1 too. I'm optimistic this is the start for the cycle. I also did my first dKh test and it turns out I'm right at about 11 dKh which is much higher than I personally want and I'm aiming for about the 8 range. I need to figure out how to lower this.
Current Goals:
-I am not trying to chase numbers, but at a minimum, I will have to lower my temp a bit more to about 73 for the Jellies, I do need to lower my salinity from about 1.026 to about 1.023 or so, and I need a more consistent pH of about 8.1-8.2 which I just can't seem to be trending towards right now (despite the bubbler, open windows/doors, and added buffer). I am considering a large water change (30-50%) with a gravel clean to clean up any debris or problems in the sand, clear the high Alk a bit and maybe give better water for the cycle to continue in.
Future Plans:
-Install an ATO, install a skimmer, and install a mini refugium.
Some Encountered Problems:
-Difficulty in estimating if current spray bar is adequate for the flow I need in the aquarium, and whether it will damage jellies from its jets. Other thoughts and DIY have come to mind so I may modify at a later date.
-The Hermit crabs love climbing the netting to the top, and sometimes over, putting them into an area I don't want them in the main tank. I used to move them when I saw them. Now I'm seeing if any ever appear trapped. I actively saw one climb back over from the other side with little difficulty so this may not be as dire as I initially thought.
-Brine Shrimp Hatchery still running a little cool for my liking.
-May not have needed to upgrade my return pump, but time will tell.
Photos to come when I can.
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