Lethargic Corydoras?

[DreaminginBlue]

I added two new corydoras to my tank a week ago. I gave them a preventative bath and observed them; they seemed healthy and active. Everything has been fine since then, they love their little school of five and as soon I can they'll have three more buddies.
I give them Hikari sinking wafers (the kind made out of shrimp and other things) every other day, and they get half of an algae wafer every Sunday. Today's piece of algae wafer ended up being a bit big, but they worked on it and finished it up. Afterwards, they were really lethargic and wouldn't move.
They seem a bit better now, as it's been a few hours, but I'm wondering if they were just resting because they were full or if I need to be concerned about illness? As of now, they'll rummage around in the substrate as usual, but then lay still for a while. The periods that they rest seem to be lessening in length.
My water parameters are great, no ammonia, no nitrite, nitrate less than 10 ppm. I really hope they aren't sick... and if they are, how do I figure out what's wrong/treat them? They're scaleless, so I know they can't have certain medications.
Should I just observe them and see how they are?
I have my QT tank but it's not set up yet, but when it's done cycling I can quarantine them if necessary.

 

[Coursair]

What size tank are they in ?
What species of Cory ?
What is the temp ?

Some WC Cories can come in with internal parasites. PraziPro is a Med some folks use. In a QT tank.

For now ? I'd cut out feeding algae wafers. Live foods are best. Frozen food is next best.

Omega One Shrimp Pellets and Color Flakes are my main processes foods.
Repashy has great gel foods that sink also.

Cories will eat Algae wafers, but main diet should be meat based.

If you have Pandas, watch your temps. They often die off in warmer tanks.

Make sure there is enough flow to move detritus at the bottom. Or gently wave your water change hose in a circle to stir up and remove gunk without sucking up sand.

They may not be sick. Maybe just over full. See how they do in the next 24hours.

 

[DreaminginBlue]

Tank is 26 gallon bowfront.
They are longfin panda corydoras.
The temperature is 76 F.
I just bought some omega one shrimp pellets today, going to try to incorporate those into feedings. I did some research before buying the corys and saw that they're mostly carnivores, so that's why they mostly get the hikari sinking wafers, which have shrimp and other meat in them. I only give them algae wafers one a week just to help with nutrition, but I can do it once every two weeks instead if that is better.
I am nervous about using live food, but I do feed frozen brine shrimp, daphnia, and bloodworms. The corys rarely get any, as my tetras eat it all, and on the off chance some does make it to the ground, then they are able to have some. Do you know of any way to ensure that more gets to the bottom for the corys?
I did a 50% water change yesterday and substrate is clean.
Thank you for all the help.

 

[BBradbury]

Dre...

If your fish aren't acting normally, this is a water problem. It's time to look at your water change routine. Smaller tanks need more water changes, because fish waste builds up faster than larger tanks and will stress your fishes' immune system. Stress will result in sickness. Pretty simple.

Your 26 gallon needs most of the water removed and replaced every 4 to 5 days, no slacking. Corys aren't naturally hardy fish and won't tolerate even traces of nitrogen in their tank water. Nitrogen is dissolved fish waste. Keep this stuff out of the tank water by doing your water changes faithfully and your Corys will be more active.

B

 

[DreaminginBlue]

Okay, thanks for the advice. Do you think 50% water changes every 5 days is enough? That's what I've been doing. They started acting weird the day after I did a water change. I tested and everything looks great, nitrates below 10 ppm.

 

[BBradbury]

Dre...

It takes time for dissolved waste material to build up to a toxic level. The more water there is in the tank the longer it takes waste to build to the point it starts to affect your fishes' general health. Gradually increase your water changes to the point you remove most of the old water. 60 percent or more every few days is very good. This way you remove most of the dissolved wastes and what's left is diluted to a very safe level in all the new, treated tap water.

Your fish should recover their energy in a short time. The key to keeping fish is to maintain a steady water chemistry and that's done through a steady water change routine.

B

 

[DreaminginBlue]

Okay, thank you.

 

[kb0526]

Adding live easy to grow plants ( i.e amazon swords, eldoea, anubius) will also help balance your tank and consume some of that nitrogen from your fish waste

 

[DreaminginBlue]

Thanks for the tip! I have live plants, like anubias, wisteria, java fern, etc.
I love them and I'm so glad I went the live plants route!