Cory and Goldfish

I am setting up a 20 gallon high tank and was wondering if I can put two goldfish in with four Cory catfish.

No. Corys are South American, and need warm water(high 70's to low 80's) Goldfish are cold water. Beyond that, bioload of messy fish are detrimental to Cory's overall well being

I would also agree with Suprd. Goldfish are cold water, and corydoras are tropical. You'll always have one unhappy type of fish in that situation. Really the minimum tank size for a single gold fish should be about 30 gallons, and an additional 10 gallons per fish. They are big waste producing fish.

There are lots of other great options you could select with your corydoras though .

Thanks for the help, I'll stay away from Goldfish And probably go with four Cory Dora's and something else.

I've decided to set my tank up with Corydora's. I'm 30 minutes from the closest Pet shop. Would it be okay to get four at once or is that to many.

If your tank is cycled, you can easily put 4 at once. I would even get 6.

Well I have the gravel in my tank now and the water has been in the tank and running through the filter for a month. My PH is 7.6 and the ammonia is 0 . So tomorrow I think I'll drive to Niagara falls , PetSmart and get six Corydoras.

I can't remember if you added some cycled media to the filter or added fish flakes or ammonia to jumpstart the cycle?

I put in fish flakes. I don't have the Nitrite and Nitrate kit but I'm hoping it will be okay. Someone gave me some Betta food. Do you think I can give it to Corydoras.

As long as it sinks, yes

Going tomorrow to pick up six Cora's and a Betta fish.

Well went to PetSmart and got 3 Red tail black Variatus and 3 Sunburst wag platy. Not the cories I wanted.

werwer2016 wrote:Well went to PetSmart and got 3 Red tail black Variatus and 3 Sunburst wag platy. Not the cories I wanted.

Love to see some photos.

Just keep doing some good sized water changes for a few days, as it will take a little bit of time for sufficient bacteria populations to catch up to the bioload of the tank.

You have a big enough tank to probably support a nice group (ideally 6ish, they are social fish) of small bodied corydoras. I'd just make sure everything is on the up and up with your new residents (ideally at least a couple of weeks).

One thought, how smooth is the gravel in your tank? Corydoras need substrate to be smooth (IE sand, smooth gravel), as they have sensitive barbels that can get damaged with coarse substrate.

How often should I do water changes and how much. The gravel I have is a course gravel.

werwer2016 wrote:How often should I do water changes and how much. The gravel I have is a course gravel.

I would suggest the greater the volume the better, the greater the frequency the better. Just as a reference, I would be doing it probably 20-40% every 1-3 days. Particularly during the first week or two. Just monitor the fish for signs of distress (red gills, lethargy, not eating, etc), if you see any of these, increase that frequency/amount. I like doing this anytime I add new fish, as it takes a few days for bacteria populations to catch up to the load in the tank. An absence or insufficient colony of bacteria may mean excess ammonia or nitrite in the tank, which is obviously bad for the fish. I'd just be careful, as you haven't had any occupants in there yet, and you aren't 100% sure you are fully cycled. I would also be very sparing with the feeding for the fish (not more than they eat in a 2 minute period, probably 4 to 6 times a week).

Was there a specific method you followed for your fishless cycling process?

The coarse gravel may be an issue for the corydoras unfortunately. Corydoras dig around with their snouts quite a bit, as a result, those barbels (whisker like sensory organs) get damaged and wear down. I too had relatively coarse substrate when I first kept Corydoras, and it didn't go particularly successfully. I even ended up creating small "islands" of sand on shallow plates, they definitely preferred hanging around on those, but really the damage was already done. I ended up eventually switching out the substrate for a smooth, smaller sized gravel, which has been great for my current occupants with barbels (dwarf loaches).


Congrats on your new occupants, can't wait to see some photos, and hear how they are doing.

Thanks CAAIndie for the help. This is all new to me. I'll try the water changes every two or three days. How much Prime should I put in when I do the water changes. I also have stress coat plus and a product called clarity that I was giving. Oh and Top Fin Bacteria supplement. I had a tank before with mollies and Corydora's but it kept getting cloudy all the time. I think I was over feeding them. I tried to cut and paste some pictures but they didn't work.

Hi werwer2016. The most common problem with new tanks is stabilizing them. Even veteran fishkeepers have problems establishing tanks. Keep the water changes every few days; the cloudiness will mean that you are still cycling. The buildup will occur very quickly so keep an eye on your tank every day for cloudiness. Most recently introduced fish will be stressed when put into a newly established tank and they are prone to any opportunistic disease that happens to be in the water at the time, whether it is ick, velvet etc. The best action right now is water changes every few days (don't forget the water conditioner).

I have Prime, Bacteria Supplement and Stress Coat Plus. Which one is the best to use for water changes and if I do a 25 % water change how much should I use.

werwer2016 wrote:I have Prime, Bacteria Supplement and Stress Coat Plus. Which one is the best to use for water changes and if I do a 25 % water change how much should I use.

Prime is the only thing I would worry about putting in. Just follow the label (my 26 gallon takes about half a cap). Use this with each water change. It's a good dechlorinator and does convert ammonia to ammonium (which is less toxic than ammonia).

When I add the Prime do I add the amount for the tank or for what I take out. I believe that it is two drops per gallon. So if I do a 25% water change should I be putting 10 drops of Prime in or more.

Dose for the entire tank volume, not just new water.

Thanks for the information Suprd71.