geh4

Like pamd, Trio123, and kevline, I'm having trouble keeping some corys alive. I have a 20 gal tank with one pair of dwarf gouramis (male and female), 9 Harlequin rasboras, and 3 Clown loaches (about 2" long ea). I bought some panda corys from my LFS and they all died within a month. I also have a 10 gal tank with guppies (7), neon tetras (9), and two corydoras sterbai. I added 5 albino corys, two of which committed suicide by leaping out of the tank in the night (there is a hood, but they got out through the gap next to the filter). Of the remaining 3, one became egg bound and died, one laid 5 batches of unfertilized eggs and then died, and one is still alive. I added four more albinos to keep this one company, but two of the new ones died within a week.

Tank specs for both 10 and 20 gal: temp = 26C (constant - I calibrate the thermometers once a month), ammonia 0, nitrite 0, pH 7.2, GH 120 ppm CaCO3, KH 80 ppm CaCO3 (water quality tests done every fortnight), live Val growing like crazy, filter, large airstone, 25% water changes twice a week (new water at the same temp as tank water and treated with AquaPlus to remove chlorine etc.) Both the tanks were well cycled before adding the corys. The corydoras sterbai have been unaffected by all of this. All corys are fed algae pellets and bottom-feeder pellets, and there is a healthy algae lawn growing on the back of both aquaria they can graze on at any time. The person I deal with at the LFS breeds discus and other South American fish, and she is at a loss to explain what is happening.

Can anyone help me?

Thanks, and sorry about the length.

sirdarksol

No worries about post length. The more info the better.
Cories (and I think Panda Cories in particular) are very susceptible to poor water quality.
Unfortunately, both tanks appear to be overstocked. It may be very difficult to keep cories alive in these tanks, and your other fish are likely to develop problems, as well (especially as the clown loaches, who can get to be a foot long, grow up).
You don't have nitrate listed on your water parameters. I would bet that it is pretty high in both tanks and would bet that this is at least part of the problem.

Shawnie

Hi geh4....sorry about the loss of your fish its totally frustrating when our babies die......somethings im noticing is first thing i see is no reading for nitrates?? what test kit do you use? could the kit be wrong on the ammonia? im thinking because IMO the tanks are overstocked, that the nitrates mite be high and maybe the ammonia readings mite be off?...adding so many fish at a time could have caused some stress ...im sure some others will be along to help some more ..I hope things get better!

geh4

Thanks to all for the advice. I am using the Hagen/Nutrafin test kits for everything - pH, water hardness, ammonia, nitrite. Believe it or not, I've been told (and read in some books) that nitrate levels are less important than ammonia and nitrite, and so have never tested for it. I'll nip out to my LFS tomorrow and grab a nitrate test kit. Will let you know how things turn out. I knew the Clown loaches got quite big, but was under the impression that it took a while (about 2 years?). I had planned on getting a bigger tank (min. 150 gal) once I've saved up some money, but it looks like that may happen sooner rather than later. Cheers!

sirdarksol

Nitrates aren't as deadly as ammonia or nitrites, but they should be kept below 20 (some say 10) or they will stress the fish.

Lucy

Hi geh4,
I'm sorry about your loss.
Keep your eye on Craig's List, people are spring cleaning and there have been a lot of good deal on there, especially with the larger tanks.
Good luck.

geh4

Hi all,

Checked the nitrates today (Hagen/Nutrafin test kit) and the levels were 5 ppm (mg/L), so it looks like all the water parameters are ok. Very mysterious. The person I deal with at the LFS said a few of the albino corys died over the weekend, so it might just be a problem with the batch. In any case, I have a credit for the fish. A few other people also suggested Craig's List for good deals on aquarium stuff, so I'll definitely be looking into it.

Thanks again to all who replied.