[snake90890]

Hey, everyone I've been trying the Walstad method for a year now almost, but I feel as though right when things are going better something goes wrong. The plants are doing well finally and growing with new growth. Ammonia is 0 mostly due to plant growth, pH 7.4, temp 74, 10-gallon. I've had Corydora habrosus the whole time I've been doing this type of tank. I got 6 at the very beginning and over time only two have stuck around to today. I even got another 4 at some point 3 months ago to try and bring the school back up. All 4 new ones have died but these two fish have been resilient and stuck around. I also have cherry shrimp, ramshorn, and MTS that are all doing fine and breeding like crazy.

Now I'm worried because one of Cories are literally doing backflips. I'm thinking that it's due to constipation, as it seems most of my fish that have died seem to have died from a fish bladder issue. Seems like half my fish die within a few weeks when I get them and then if not then a few months later due to a swim bladder issue. I don't know what I'm doing wrong, I keep thinking it's because the fish are sifting the sand and eating stuff they shouldn't or maybe its the food. I don't know what to do any help would be amazing I just don't want to lose any more fish.


Video of cory doing backflips

 

[mistergreen]

Bloat isn’t necessarily constipation. It’s usually infection of the organs. It could be the reason for your Cory boing back flips. It sounds like you have some chronic mycobacterium in your tank. I would siphon out as much surface mulm as I can and leave it fishless for a while. If you can add a uv sterilizer, it would be even better.

 

[snake90890]

Would I have to take out all the shrimp and snails too?

 

[snake90890]

Also with Walstad tanks does the sand need to be cleaned? The mulm removed?

 

[mistergreen]

You do what you can. You’ll never wipe out all the myco, just reduce their number. They live on organic matter Like mulm and surface scum.

 

[snake90890]

Are shrimp and snails susceptible?

 

[dwalstad]

Don't worry about the snails and shrimp.

Saw the video. Sorry about your fish. I would not assume any cause at this point. My male guppies swelled up and died a few days later. I bred the problem out of my guppies (by outcrossing and careful selection), so it was not mycobacteriosis. (You really need a vet diagnosis to say it is mycobacteriosis.)

It could be that these Corys are vulnerable to general bacterial infections. Since they are bottom-dwellers and exposed to substrate bacteria, they are going to get a continuous dose. They coulld also be stressed by anaerobic substrate toxins. Your letter supports my notion that bottom-dwelling fish are going to need a little adjustment to a typical Walstad tank.

In looking at the picture of your tank, I don't see any filter or aerator. Water is a little cloudy which suggests bacteria. Plants are not doing well enough to cover the tank bottom the way they should.
I would get more water circulation in this tank--a small submerged pump. If you can move it down towards the bottom where the current 'blows' over the substrate, that would be ideal. This will encourage aerobic bacteria in your substrate to quickly recycle debris. This is a better long-term solution than cleaning the gravel.

Also, that thick layer of duckweed is holding your rooted plants back--taking the light from them. I would thin it out to 1/4.

Another idea: Quite possibly you could add an HOB (Hang-on-the-Back) filter. This would increase the health of your Corys, plus the spillway would get rid of the duckweed. There's some chance that the rooted plants might also grow better with more light, more water circulation. If you want floating plants, use bigger ones than duckweed (e.g., Frogbit).

I don't think you have anything to lose here by trying some new things. Mistergreen's suggestion of a UV filter is not a bad idea. It would kill excessive bacteria of all kinds AND get some water circulation in this tank.

 

[snake90890]

Don't worry about the snails and shrimp.

Saw the video. Sorry about your fish. I would not assume any cause at this point. My male guppies swelled up and died a few days later. I bred the problem out of my guppies (by outcrossing and careful selection), so it was not mycobacteriosis. (You really need a vet diagnosis to say it is mycobacteriosis.)

It could be that these Corys are vulnerable to general bacterial infections. Since they are bottom-dwellers and exposed to substrate bacteria, they are going to get a continuous dose. They could also be stressed by anaerobic substrate toxins. Your letter supports my notion that bottom-dwelling fish are going to need a little adjustment to a typical Walstad tank.

In looking at the picture of your tank, I don't see any filter or aerator. Water is a little cloudy which suggests bacteria. Plants are not doing well enough to cover the tank bottom the way they should.
I would get more water circulation in this tank--a small submerged pump. If you can move it down towards the bottom where the current 'blows' over the substrate, that would be ideal. This will encourage aerobic bacteria in your substrate to quickly recycle debris. This is a better long-term solution than cleaning the gravel.

Also, that thick layer of duckweed is holding your rooted plants back--taking the light from them. I would thin it out to 1/4.

Another idea: Quite possibly you could add an HOB (Hang-on-the-Back) filter. This would increase the health of your Corys, plus the spillway would get rid of the duckweed. There's some chance that the rooted plants might also grow better with more light, more water circulation. If you want floating plants, use bigger ones than duckweed (e.g., Frogbit).

I don't think you have anything to lose here by trying some new things. Mistergreen's suggestion of a UV filter is not a bad idea. It would kill excessive bacteria of all kinds AND get some water circulation in this tank.

Thank you for the comment, Diana. I'm glad I don't have mycobacteria. I have a little 5W submersible pump that I put in the bottom left back hand corner to blow across the back of the tank along the substrate. I don't know if the flow is too strong or not it is 95GPH at full speed and it is at halfway now? I will try and get some big floaters instead of duckweed. I ordered water lettuce at the start of this tank, but I guess they just sent me duckweed and like two water lettuce.
I'm trying to keep cutting and replanting the plants in the tank so that over time more and more ground is covered it just takes some time. The dwarf sag is sending runners which is awesome and the cabomba is growing really well. I just cut and replanted some of the taller plants and removed a lot of the duckweed.

I was hoping to breed these cories, but it just didn't seem to work out. Could you explain a bit more how you outcrossed your guppies? Did you just buy fish from several places or keep two tanks?

Quick video of the flow currently
New install of 95GHP Pump

 

[snake90890]

Just did a 50% water change too

 

[dwalstad]

I was hoping to breed these cories, but it just didn't seem to work out. Could you explain a bit more how you outcrossed your guppies? Did you just buy fish from several places or keep two tanks?
Quick video of the flow currently
New install of 95GHP Pump

Pump looks fine. Water movement good. Not too fast, not too slow. Replanting good. Water change good. Hopefully, the water will clear up further and you start getting some better plant growth.
You've got a bunch of pearl grass floating at the top. That's a nice plant. I would plant it as best you can. Just lock it down with a stone or gravel piece. You don't need to plant it with surgical tweezers.
Also, I would lower the water line. You've got a lot of cloudy water for the light to go through before it reaches those stem plants. I measured light (PAR) in my tanks. Measurements 6 inches below the surface were 1/3 to 1/10 of what I measured at the the water surface-- and the water in my tanks is clear, not cloudy. You could lower the water level by half temporarily.

I wrote about breeding for fitness in my article 'Guppy Longevity', available on my website. Yes, I outcrossed my Blue Grass strain, the one with the constipation problem, with swordtail guppies. I had 8 tanks at the time, but could do it in one. Female Blue Grass kept with male swordtail guppies.
I would get a book or seek out information from people who breed Cories. I have no experience with them. But I would get your tank in better shape first. If this tank is a year old, something is holding plant growth back?

 

[snake90890]

I'm thinking there isn't too much growth because there isn't enough of a bio-load. I was only feeding at most 5 fish once every three days as I didn't want to overfeed. I did this to prevent them from dying like they were, it didn't help. I have been feeding more recently though at least once every two days, sometimes everyday. I say this in part because every time I check ammonia in the tank there isn't any, until a little while ago when a fish died and was in the tank for 3 days. There was an ammonia "spike", it never got to more than .5ppm but I did a 50% water change anyway and the plants seemed to be doing better with a little more ammonia provided to them. This of course could be wrong, but its an idea. Maybe this combined with lower light levels at the bottom of the tank.

I turned my light brightness up all the way, I took some of the water out from the tank and planted the pearl weed.

Thank you for the advice and assistance. I will go read your article on Guppies.

 

[snake90890]

Update: Fish survived, replaced duckweed with frog bit, plants are growing more and more but water is still cloudy. My flow got turned down somehow and it was clear for a while, until noticed and turned the flow back up and then instant cloudiness again. I'm trying to just be patient and hope eventually with more and more plants that the tank will become clear.

 

[maico996]

Did your flow get turned off, or just down? If down and your water cleared up, then I'd go with that flow setting.

 

[snake90890]

Did your flow get turned off, or just down? If down and your water cleared up, then I'd go with that flow setting.

It wasn't off but it was barely on. It is at around 3/4 blast and got turned down to 1/4 blast on my 95gph pump, so it was very low flow.

 

[johnwesley0]

A year-old NPT is going to have all sorts of detritus (mine does.) It settles on the bottom of your tank where it may serve as a source of nutrients for plants and microorganisms - and also release excessive CO2 (I've learned this the hard way) or you can remove it by vacuuming. Right now, it looks like it is just being kept in suspension by the constant flow from the powerhead. Some species of tropical fish (like a. borelli) get a kick out of poking around muck. To cories a mucky, mulmy substrate may pose a significant danger. To me, your tank looks perfectly normal. You just have to decide what's best for your livestock.

 

[maico996]

It wasn't off but it was barely on. It is at around 3/4 blast and got turned down to 1/4 blast on my 95gph pump, so it was very low flow.

I'd leave it at the 1/4 setting. You don't really need a lot of flow anyway for such a small tank.

 

[dwalstad]

Update: Fish survived, replaced duckweed with frog bit, plants are growing more and more but water is still cloudy. My flow got turned down somehow and it was clear for a while, until noticed and turned the flow back up and then instant cloudiness again. I'm trying to just be patient and hope eventually with more and more plants that the tank will become clear.

You turned flow down and water cleared? You turned flow up and the water became cloudy? Why don't you just turn flow off again and see what happens.
I have no flow in any of my 9 tanks. I only add flow if I see that my fish--or shrimp-- need it.
If your water cloudiness is from micro-algae, your plants would be better off with no flow, no algae. (The algae will drive up the pH and take CO2 and nutrients from plants.)
That said, it looks like you're getting some decent plant growth. Adding FrogBit was a good idea.

 

[snake90890]

Ok I just turned down the flow to almost nothing and we shall see if the water clears up at all! I will keep you posted on what happens. The other thing I was thinking was maybe I was overfeeding and that was causing the cloudiness. I feed usually once every two days a pinch of micro-pellets or an algae wafer crushed up. I was thinking potentially the algae wafer was causing the cloudiness.

Thank you again for all the help everyone.

 

[dwalstad]

Ok I just turned down the flow to almost nothing and we shall see if the water clears up at all! I will keep you posted on what happens. The other thing I was thinking was maybe I was overfeeding and that was causing the cloudiness. I feed usually once every two days a pinch of micro-pellets or an algae wafer crushed up. I was thinking potentially the algae wafer was causing the cloudiness.

I would also do a major water change (70% or more)--at least once. (The water change will get rid of this dense suspended algae culture and hopefully tip the balance towards the submerged plants before the suspended algae can crank up again.)

It doesn't sound like you are overfeeding. (I dump in food 2-3 times a day.)