Cory cats dying off

Long post is long!! I'm losing it a bit! New to the forum and to (kind of properly - I'm trying) fish keeping - and I'm on a massive struggle bus when it comes to keeping Cory cats alive! My mom got me into bettas and corys, so I got some of my own... And while my betta is thriving in a 20 gallon tank, my Cory cats are definitely not... In fact, the minute they drop into the tank they go from active/happy to lethargic within seconds - it's bizarre. I've currently lost three. As far as I can tell with water tests, my water is fine - nitrites at 0, nitrates low, ammonia is very low as well (I believe about 0.2 on the API reagent test?). My water is hard, but not so much that a Cory cat would take notice, and my pH is about 7.5.

I cycled the tank before adding fish and have had these fish in for about 2-3 weeks now - I was planning on 30% water changes weekly, but with the Cory cats not being a clean up crew things build up fast... Most recently, I did a huge water change (as low as I could and felt comfortable doing - maybe about 55%? And less than a week ago did a 40% - I was originally adding betta conditioner and a very small amount of bacteria booster, but with my mom's Cory cats thriving, in their temporary 10 gal (these things are PSYCHOS - they never rest!) we decided to go her route - so I've removed as much as possible over the last week and a half and just add Betta aqua safe to the water now). This seemed to pick up my Cory cats for a minute, but one of my peppered ones (which was the pair that was really starting to pick up) suddenly died... Energetic one minute, dead the next. With my main concern originally being the water, I have been doing frequent and small water changes, but now I just can't figure it out... My water test's fine, my betta is thriving.

I had 3 albino cats, one died early on... One of the two remaining is incredibly swollen all around which I'm thinking is dropsy, and the other also seemed a bit bloated but after my 55% water change that has completely disappeared. My peppered Cory's were incredibly active after the change for a couple of hours, then one suddenly died... Since day one, none of these fish have been interested in food, they get into my tank and seem to immediately start a very slow death.

Also, stupid alert, we put my remaining two albinos in with my mom's albinos to see if maybe it was a schooling issue.... Within 2 mins her Cory's, for the first time EVER, just sat at the bottom of the tank doing nothing.... We took my albinos out, and within 10 mins her Cory's were back to normal. We're completely confused by this - by my Cory cats...

Could this potentially be a gravel issue? My mom and I also have the same brand gravel, just different colors (and she adds marbles to hers as well) - we literally have the same tank, mine is just double the size.

 

Hi, sorry about your fish,

You may be right, it could have been dropsy.. but it could also be stress. When you just plop a fish in a new environment and then take them out after a little while, it usually leads to problems... the only thing I can think of is that their tiny "whisker's" or barbles, can wear down over time from the substrate being too jagged and sharp and they can't eat.. Some people say sand is the best thing for cory. Temperature can also play a big roll as well as PH balance. Not sure why exactly why yours have been dying (maybe some one can chime in) and it is weird about your mom's fish acting that way when you put yours in but try the things I mentioned and check all your parameters again, you may have a faulty test kit. Good luck!

Ps. i just noticed, you shouldn't have any ammonia at all, are you sure you're cycled?

 

You may be right, it could have been dropsy.. but it could also be stress. When you just plop a fish in a new environment and then take them out after a little while, it usually leads to problems... the only thing I can think of is that their tiny "whisker's" or barbles, can wear down over time from the substrate being too jagged and sharp. Some people say sand is the best thing for cory. Temperature can also play a big roll as well as PH balance. Not sure why exactly why yours have been dying (maybe some one can chime in) and it is weird about your mom's fish acting that way when you put yours in but try the things I mentioned and check all your parameters again, you may have a faulty test kit. Good luck!

I was super careful about integrating... 15 mins floating, taking out store water/putting in tank water - the hyper integration method... My betta actually got the short end of the integration stick, his cup flipped upside down between trips for the Cory's after 15 mins, so we just let him go at that point. My temp was at 78, but I thought maybe that was too high and making them lethargic, so I've brought it down to 75 - I'm reluctant to go lower since I live in a pretty chilly basement, but the lowest it ever gets is 75.0 (usually stays around 75.5)

The tank switch doesn't seem to have changed my albinos at all - and my dropsy suspect was looking a bit funny before I put him in my mom's tank... They're back in my tank doing the same as usual Their barbels also look exactly the same as they did day one - I have been debating switching to sand, but since I'm planning to size up with my tank I'm thinking it will at the very least be easier on my betta to only go through that whole ordeal once. Is there a relatively easy way of switching substrates in a cycled tank? I've read a few articles, and it seems almost like it would be easier to just set up a new tank.

I'll definitely look into getting a new test kit - It's just very frustrating having apparently the same water parameters as my mom, who has a thriving little group... And it's just heartbreaking watching these little guys suffer (I've been seriously debating euthanasia, especially for my bloated albino... And then I have lone cats and it just goes in this ugly circle - and that also obliterates my chances of finding the problem and/or solution, if one exists).

 

When you say "apparently" the same test results. What do you mean?

 

Is there a relatively easy way of switching substrates in a cycled tank?

Honestly it can be done, but i personally wouldn't.

 

When you say "apparently" the same test results. What do you mean?

If the test is faulty - my tank is apparently the same as my mom's, according to our tests and by reason (same substrate, filters, water, and water treatment now), but my Cory's are ill and hers aren't, so something must be off. The only difference in our tests currently are ammonia levels - hers are slightly higher, but the 10 gal is crowded with a betta and 2 albino Cory's (so it's just dealing with that until they get into the 30 gallon)

 

Honestly it can be done, but i personally wouldn't.

That's what I thought - there's such a huge difference in fish keeping depending on who you ask - but the consistent things have been tank cycling and substrate changing