Ricefish Pond Disaster!

[The Kentucky Mermaid]

Hello everyone! I have been keeping fish for over 20 years, but this is only my second attempt at summer tubbing. Last year, I had a planted whiskey barrel guppy pond, and they did great and had lots of babies! I have recently fallen in love with Medaka/Japanese Ricefish, and have been reading and watching everything I can about them for months! They are supposed to be hardy, adaptable, and perfect for ponds and container gardens. We dug a 30 gallon pond at the beginning of April, put plants, rocks, and driftwood in. We added beneficial bacteria, and dechlorinator, and left it be for about a month. In the meantime, I got a school of beautiful platinum ricefish, quarantined them with meds, and observed them closely for several more weeks. They were doing great and the female even had eggs! A few days ago, I introduced all 8 ricefish to the pond. I acclimated them slowly by pouring pond water into their container of tank water, over the course of an hour. I sat by the pond for the next few days watching them swim happily and gobble mosquito larvae! They were so beautiful! Then, on the 3rd day...disaster! Only 1 medaka came up to greet me yesterday morning. I found the rest dead in the bottom of the pond, and assume the last one has died as well. I was heartbroken! I buried them in the garden and tested the water. 1ppm ammonia, 0 Ni, 0 Na. I didn't think water changes were necessary in ponds/summer tubs, but do I need to do them? What do I do to fix this problem? Or do I just wait...and test every week? When is it safe to try again? I really thought ricefish were super hardy and could tolerate most anything. I am shocked and devastated to loose all of them. They were showing no signs of distress. I really want to try ricefish again, but I won't put all of them outdoors next time (or all of my eggs in one basket). I thought my pond would be ready for fish by now. Please help?! Thank you!

 

[Zenzo]

I am sorry that you lost your fish. It sounds like there may have been a crash or an ammonia spike. This can happen if you add a bunch of fish at one time and the bacteria and plants are not able to keep up with the newly introduced load. I would suggest restarting and giving the pond some time to balance out. While summer tubs require less water changes than an inside aquarium (usually due to water volume, plant growth, and rain), they still need to be maintained with either partial water changes when needed or top-offs. Good luck!

[CalmedByFish]

Sorry about your fish. The pond is super cute.

With 1 ammonia, but 0 nitrite and nitrate, it makes me wonder if the bacteria was up for the challenge. But that's just a guess. Maybe, if you try again, add bacteria at the same that you add fish, even if you also added some beforehand. 

I know Cory put out at least one video on summer tubs. You could probably search the word on the YouTube channel and easily find it. Might help. 

[The Kentucky Mermaid]

Thank you everyone for the advice!

I will give it some time, keep testing, and water change as needed! 

[Diving Aquarist]

Sorry to hear about your fish. This is the biggest fear I have when I put my fish in the tubs for the summer.

Do you know what the temperature is in the tub? If it is in full sun for too long, the temperature might just get too high. The ammonia could be from the dead fish. Warm water speeds decay up quite a bit. Last year I had one of my 90L tubs (roughly 20G) in full sun. For a few consecutive warm, sunny days, I could measure the temperature being close to 100F. I'd wager that would be enough to cook most fish, or the lack of oxigen in the water could cause death. It killed all the shrimp I had in there. Yours was in the ground, and that should isolate a bit, but temperature might still have been a factor. My understanding is that a well planted tub shouldn't need a filter, since the plants would suck up the ammonia very quickly. The plants are the key in the whole thing. I only started tubbing myself last year, so I'm far from experienced enough to know common issues firsthand. I did somewhat obsessively follow people that were tubbing on YT,and read a whole bunch about it for years now. I can only put small tubs on my balcony (my neighbor below me wouldn't like it if it collapsed under the weight), so temperature is a big challenge, simply due to the volume.

I would say that your fish choice was correct from the hardiness point of view (just like white cloud minnows, for example), that's why I'm leaning towards a different reason for this disaster.

Maybe it's just me, but I don't think 8 small fish in a nicely planted 30G tub can create a deadly amount of waste in 3 days.

[The Kentucky Mermaid]

Thank you Diving Aquarist! My pond gets morning to noon sun, then is shaded the rest of the day by the eave of the house. Right now it is 75°. I do have a sponge filter/waterfall pump for filtration and oxygenation, on gentle flow, since ricefish don't like current. I too watched every summer tubbing video I could find! Fishkeeping is always a learning process, no matter how long you have been in the hobby. That is what keeps it interesting! I am grateful for this community and all the folks at Aquarium Co-op! Thank you all for the feedback!

 

Edited May 27, 2021 by The Kentucky Mermaid

[GardenStateGoldfish]

I am sorry for your loss 😞 what was your PH? I notice you set up the tub in april but only recently added the rice fish, I would think that the ammonia your testing may only be a result of the loss and not what may have caused the loss. Were there any other circumstances that may have contributed? how often were you adding in the bottled BB? just the day they were added or daily? those can often spoil. 

Another thought looking at it, your water level does appear to be lower, how much sun does your pond get? could there have been a large temperature swing that heated the water too quickly from overnight to day time? Black in the sun heats up quickly. 

Beautiful pond! Rice fish are mostly hardy, however some of the fancier types are more fragile, don't give up on summer tubing, it is so fun and refreshing to do seasonal stuff with your fish. 

I recommend getting Dr. Ted Coletti's The Tub Pond Handbook, its got literally everything you need to know about summer tubs, he's been summer tubbing for decades. If you don't want to purchase anything, then you can hear a lot of good tips in a youtube video he did on the pond hunter radio (I think episode 52, maybe 53) which is about an hour long but dose cover some secret killers. 



 

[The Kentucky Mermaid]

I will definitely check out "The Tub Pond Handbook" and related videos. I will monitor the parameters closely and keep an eye on the temps. Thank you again, to all of you, for your help!!!

[RockMongler]

Did you (or perhaps a nearby neighbor) do any chemical treatments in your yard in the last few days?  Say, grass fertilizer, or a pest treatment for ants/termites/grubs?

I would suspect, given the volume of plants you have in the tub and the relatively low number of fish, that it might not have been the ammonia/nitrite/nitrate, but some other contaminant that got into the tub. But, that might be harder to properly test for.  That is what I would suspect outside of extreme temperatures.

[The Kentucky Mermaid]

I practice organic gardening and never spray anything in my yard, garden ect. The pond is up against our garage, in my rose garden, not close to any of the neighbor's fences. They do not spray either, as far as I can tell. You never know though. I did check my PH today, here are the results, the lower PH 6.0 is from the pond, the higher is the water in the tank the fish were originally in. I know the driftwood and fallen leaves could be pushing it down pretty low. It has been raining quite a bit today as well. Do you think that could be part of the problem? Should I try to buffer it?

[Pete]

I wouldn't try chasing pH, but you might try adding some crushed coral to the pond to help bring it up a little bit. 

It seems like you're on the right track, monitoring temps and water parameters and then letting nature play out. Consider adding even more plants than what you've got in the photos. I'm a huge fan of frogbit since it's such a fast grower; plus it's great for fry. 

[Grubhead]

I had read that water hyacinth is very useful in these pods to take up nutrients and provide places for eggs and fry, not that it was the lack of plants that caused your issue.

There is another post where some of us have found chlorine levels spike, with a potential issue being the material of the container, but I doubt that is the issue.

Sorry you lost your fish!

[The Kentucky Mermaid]

     After all of the helpful feedback, and further testing, I am sure my fish loss was due to LOW PH, which caused the AMMONIUM/AMMONIA spikes. I also learned from my LFS, that when the water is too acidic, it kills off all the nitrifying bacteria. This is why after adding bacteria, and a month of "seasoning" before adding any fish, the pond hadn't cycled! I am adding crushed coral and might remove some of the driftwood, if need be. I think if I can stabilise the PH, I will be moving in the right direction. Thanks all!