Gradually losing my pygmy corydoras

[dw1305]

Hi all,

Interesting Eheim filter you have there!

I quite like it <"Product Review - Eheim Aquacompact Review">, I bought it as "pre-owned" via ebay, but it had obviously never been used.

They are ugly, but relatively effective. I'm not surprised they weren't a big seller <"aquacompact"> but if you don't <"care about aesthetics">, or low flow rates, they are fine.

You can see it <"here too">.

cheers Darrel

 

[Bradders]

It's a decently planted tank judging from this Journal entry ... but yes, I would be worried about lack of nutrient distribution / flow and oxygenation with such a small filter turnover you get from a pat mini vs. the tank size and density of the plant mass. The Cory's are bottom dwellers and I can't help suspecting they may be exposed to low oxygen levels and possibly toxins from decomposing waste,

Yeah, I do agree. I know this is controversial, but at the moment, I feel like aeration and filtration have a part to play here. If it was me, I would certainly move away from that Aquael Pat Mini filtration.

 

[Katharine]

Hi @Katharine Sorry about the loss. Since you only had them for 2 weeks, I'd say they probably carried the disease from the store where you got them or they got stressed out from introduction in their new home - for instance if the water they came from varies wildly from your tank water - this alone may not be a problem if the fish is otherwise healthy but could weaken their immune system enough to make the disease they carry lethal.

@Katharine, I wonder how those cherry shrimps and Oto's are doing, are you loosing any of those?

Cheers,
Michael

The otos are doing great, I've not lost a single one, they all are eating well (including eating wafers) and are very social. I lost a few shrimp in the days after adding them which I think was due to drip acclimating them too quickly/the change in parameters, but the remaining shrimp have been fine.

The celestial pearl danios have also done well - to my knowledge I didn't lose a single one (they are hard to count) despite some being extremely small when I got them, and recently there have been fry (three of which have been in a fry box in the tank the last couple of weeks).

I'm so confused why I'm struggling so much with the corys given otos need such similar conditions and have such a reputation for being tricky. All the fish came from the same shop too , which states all fish are quarantined and dewormed prior to sale.

 

[Gerald Buswell]

Yeah, I do agree. I know this is controversial, but at the moment, I feel like aeration and filtration have a part to play here. If it was me, I would certainly move away from that Aquael Pat Mini filtration.

Yes for sure, flow is very important.

 

[MichaelJ]

The otos are doing great, I've not lost a single one, they all are eating well (including eating wafers) and are very social. I lost a few shrimp in the days after adding them which I think was due to drip acclimating them too quickly/the change in parameters, but the remaining shrimp have been fine.

Ok, that is good to know. It somewhat takes lack of oxygen or toxins off the table. The Otos' and the shrimps generally wouldn't be able to cope with such conditions either.

I'm so confused why I'm struggling so much with the corys given otos need such similar conditions and have such a reputation for being tricky. All the fish came from the same shop too ,

If the shop is nearby, I would go back to the shop and check on the stock and tank they came out of to see how they are doing. If they were diseased two weeks ago before being introduced in your tank there is a good chance the stock at the store would be decimated as well. If they all look good at the store, ask them about water parameters and how they are fed?

which states all fish are quarantined and dewormed prior to sale.

Well, that may not mean much more than the fish were not for sale for a week or two after they got them in, and they added some deworming meds to the holding tank.

Cheers,
Michael

 

[fredi]

If it’s of any consolation
I don’t usually tend to loose fish, I have been loosing Sterbai from a “known” supplier, from whom i purchased some very nice and very healthy tetras
I purchased them (sterbai and Moenkhausia costae, last year, all quarantined dosed with parasite meds), for 6 weeks
During this time 2 sterbai died, all tetras were fine, after 6 weeks the fish were all introduced to my tank, the tetras have grown like weeds, the sterbai on the other hand have not done so well (another 2 died) the remaining 3 are just not growing
I have venezuelas in same tank which continue to breed and grow
Imho I was supplied with poor quality sterbai, I won’t be purchasing from this supplier again
On the bright side, I have been told of a shop with corydoras Pulcher, must resist 😂😂

 

[G H Nelson]

@Katharine erine
Filter: aquael pat mini
Personally I wouldn't have that filter anywhere near a tank that size!
hoggie

 

[nijat11]

Probably a lot of people will blame me for this, but when I see that some fishes keep dying, I start esha 2000 + esha exit treatment for 3 days. When it done I do deworming with esha ndx. Helped me couple of times. I know we should not use any medicie before knowing what is issue, but when situation is kind of hopless, this could help.

 

[Katharine]

Your challenge here is that you need to feed the bottom feeders before the swimmers get the food! However, fish are generally greedy, in my opinion, and if you leave a tonne of food around, they will do their best to eat it. i.e. just because there is nothing left in the morning does not mean the fish have had the correct amount of food. You are looking at 1-2% of body weight for adults and 2-5% for juveniles. If you have 6 young Cory's then you are only looking only between 0.2 and 0.3 grams of food for the whole lot.

Thank you, it's helpful to put a number on roughly how much food I should be aiming for.

I've weighed out some of the algae wafers and they each weigh approximately 0.05g. Including the food I feed all the fish in a day (as who knows who eats what) comes to less than 1g (the minimum I can measure) and less than a teaspoon:

That's feeding:

9 juvenile pygmy corys
12 adult otocinclus
2 juvenile honey gourami
15 celestial pearl danios (~2 months old)
5 black panther snails
~ red cherry shrimp
1 nerite snail
Various pest snails

So I think I may actually be feeding quite a bit less than you're recommending, as you're recommending 4-6 wafers worth of food for the pygmy corys alone?

 

[Katharine]

Also (as we are advising Katherine on the next step of treatment at this point in the thread), could I point out the above? i.e. 125L aquarium with the stated inhabitants running on an Aquael Pat Mini.

Does anyone else have any concerns over the filtration capacity here?

I appreciate it's a lot less filtration than many people use - the intention is it's just for circulation really as it's a low tech walstad inspired tank, and the plants are meant to do the work! Given the other fish all seem healthy, and the water always tests zero for ammonia, nitrite and nitrate, I don't think it's what's causing the issue.

 

[Katharine]

If it’s of any consolation
I don’t usually tend to loose fish, I have been loosing Sterbai from a “known” supplier, from whom i purchased some very nice and very healthy tetras
I purchased them (sterbai and Moenkhausia costae, last year, all quarantined dosed with parasite meds), for 6 weeks
During this time 2 sterbai died, all tetras were fine, after 6 weeks the fish were all introduced to my tank, the tetras have grown like weeds, the sterbai on the other hand have not done so well (another 2 died) the remaining 3 are just not growing
I have venezuelas in same tank which continue to breed and grow
Imho I was supplied with poor quality sterbai, I won’t be purchasing from this supplier again
On the bright side, I have been told of a shop with corydoras Pulcher, must resist 😂😂

I'm sorry you've had bad luck as well! I think it's just important I do my due diligence before deciding I had bad luck. :/

I did go back to the LFS and the corys seemed okay - they were all very shy, hiding in a corner, but none seemed sick. Though one of the challenges is I don't know what "normal" looks like yet as a first time cory keeper.

 

[Katharine]

Probably a lot of people will blame me for this, but when I see that some fishes keep dying, I start esha 2000 + esha exit treatment for 3 days. When it done I do deworming with esha ndx. Helped me couple of times. I know we should not use any medicie before knowing what is issue, but when situation is kind of hopless, this could help.

Thank you. I do now have a 20 litre quarantine bucket, so I am not opposed to trying medications in a hopeful fashion if another gets sick!

 

[tam]

Do you have the venturi attachment for the mini pat? (attachment with a bit of airline). If you don't already you could pop that on and it will help with aeration. I like the mini pat - I've one in my 180l for extra circulation with a hob the other end. You might consider a second one - it's handy to have a spare anyway as they are good if you need a temp filter anywhere e.g. quaretine. I've upgraded mine with a larger sponge too for extra capacity.

I would second the live food recommendation. I was having trouble with pygmys (not the same thing mine were going pale) and they have perked up no end since adding in grindle worms and micro worms. They have gone from gradually decreasing in numbers to laying eggs. I think part of the issue is they have tiny mouths and looking more closely often the snails would be all over the food buy the time it had softened enough for the pygmys to be able to suck bits off. With the live food they get first dibs.

I'm also inclined to say as they are only two weeks in it's probably an issue around being new either something they came with or making the adjustment ... so maybe just a case of being as supportive as possible to help them adjust - so clean water, plenty of oxygen and good food.

 

[MichaelJ]

I appreciate it's a lot less filtration than many people use - the intention is it's just for circulation really as it's a low tech walstad inspired tank, and the plants are meant to do the work!

I agree with that approach - that is, to let the substrate bacteria and plants provide the bio filtration... My approach is the same. However, the turnover or strength from that filter is very low for the size of your tank and your running the risk of getting stale areas in your tank that are underserved with respect you nutrient - including oxygen. You could add another filter to increase flow in the tank. One could serve mainly the upper part and one concentrated toward the substrate level. Just an idea. Works wonderfully in my 150L tanks where I have two Pat Mini's (with air tube added) and two HOBs in each. My filters are mainly to provide flow i.e. nutrient distribution and oxygenation. They are purely mechanical (sponges only).

Cheers,
Michael

 

[Katharine]

Do you have the venturi attachment for the mini pat? (attachment with a bit of airline). If you don't already you could pop that on and it will help with aeration.

Yes I've set that up now!

I would second the live food recommendation. I was having trouble with pygmys (not the same thing mine were going pale) and they have perked up no end since adding in grindle worms and micro worms. They have gone from gradually decreasing in numbers to laying eggs. I think part of the issue is they have tiny mouths and looking more closely often the snails would be all over the food buy the time it had softened enough for the pygmys to be able to suck bits off. With the live food they get first dibs.

Yeah, I'm hoping feeding soaked decapsulated artemia will do a similar job size and nutrient-wise.

 

[Katharine]

I agree with that approach - that is, to let the substrate bacteria and plants provide the bio filtration... My approach is the same. However, the turnover or strength from that filter is very low for the size of your tank and your running the risk of getting stale areas in your tank that are underserved with respect you nutrient - including oxygen. You could add another filter to increase flow in the tank. One could serve mainly the upper part and one concentrated toward the substrate level. Just an idea. Works wonderfully in my 150L tanks where I have two Pat Mini's (with air tube added) and two HOBs in each. My filters are mainly to provide flow i.e. nutrient distribution and oxygenation. They are purely mechanical (sponges only).

Cheers,
Michael

I am curious how you tell whether the circulation is sufficient - have there been any studies on it?

 

[Katharine]

Probably a lot of people will blame me for this, but when I see that some fishes keep dying, I start esha 2000 + esha exit treatment for 3 days. When it done I do deworming with esha ndx. Helped me couple of times. I know we should not use any medicie before knowing what is issue, but when situation is kind of hopless, this could help.

Yeah now I've got what I need to setup a quarantine tank I've got no concerns really about over medicating.

Thanks for the comments all. The remaining corys seem okay today so I'm sticking with the under feeding theory, but will keep them under observation and order some esha 2000 in case any more get sick; and clean the gravel when I do water changes.

Would be interested to know how much food people are giving their corys to get a sense of how I compare.

Edit - this resource seems good - 3.3.1. Amount in Depth

 

[MichaelJ]

I am curious how you tell whether the circulation is sufficient - have there been any studies on it?

What I do is to observe for localized build up of waste, localized algae breakouts and general plant health. If all that checks out I think flow is sufficient. I always have a couple of tough spots here and there especially in extremely densely planted areas or near hardscape, but overall it's seems very good. I just have to strike a reasonable balance. Once in a while I momentarily redirect my internal filters to areas that appear underserved.

Putting filter turnover specifications vs tank size on a formula, if you have a densely planted tank, lots of hardscape etc. or suboptimal positioning of filter outlets, is a bootless errand at best in my opinion. You have to take your tanks specific conditions into account.

Cheers,
Michael

 

[fredi]

I'm sorry you've had bad luck as well! I think it's just important I do my due diligence before deciding I had bad luck. :/

I did go back to the LFS and the corys seemed okay - they were all very shy, hiding in a corner, but none seemed sick. Though one of the challenges is I don't know what "normal" looks like yet as a first time cory keeper.

There are obviously occasions when the loss of fish is down to the fish keeper. There are also times when it is not
Some fish (especially relatively high value easy to breed fish), are “produced” in poor conditions, often with no regard to varied bloodlines, with no regard to the health or vigour of the fish
Shops purchase different fish from different suppliers, I try to avoid shops which purchase these fish, i would rather pay more (which is what I thought I was doing in this case)

 

[Calamardo Tentaculos]

@Katharine sorry to hear about your fish. As you can see from my previous posts, I have been losing my pygmy cories steadily.

I wonder though whether it is a matter of PH as I see that your PH, GH and KH are nearly identical to mine.

Aside to @dw1305 , would you mind sharing your water parameters please? It could be that softer water is needed for pygmy cories, much like how caridinas require really soft water to thrive.