Will these be okay in a discus tank

[Cjbear087]

In September I am going to buy a new huge 90gal tank for discus. I currently have a small 15 gal tank, with 6 guppies, 4 cories, 1 honey gourami and some cherry shrimp. Because I can only have 1 tank, when I get my new huge one I am going to have to sell my small tank and do something with the fish in it. I don’t want to give them away, so I was wondering if these fish would be okay in a discus with their water conditions and everything.

[jwcarlson]

Most corys don't like discus temperatures, but a few do.  Sterbai is the most common.

Guppies I'm sure would "live" in that temperature, but it's pretty warm for them.  And eventually they'll probably be discus food at some point.  The shrimp will end up eaten, but they should be OK.  I'm not sure about the gourami.  Some gourami are OK with discus, I don't think I've heard honey among them, but they are peaceful, so I wouldn't think that would be a problem.  In general, though, if it's small enough for them to get a bite of, they're going to eat it.  They are cichlids and while they seem less high strung than some others... they have a little violence under the surface like all cichlids do.

You're going to need a second tank at some point because inevitably one discus won't eat or will otherwise need special attention that would be cost prohibitive or otherwise difficult to do in your main tank.  It's also a really really good idea to start with discus alone in a base bottom tank for a month or so and see how things go, make sure they're all eating, easily observe their poop, worm them for three weeks, etc.  Overall, though, if you're looking for more of a community tank-type of vibe... discus are probably a poor choice.  They're best done alone for most people as they can also be sensitive to bacteria they're not adapted to.  It leads to a phenomenon called amongst discus folks as "cross contamination" which can lead to the death of everything in the tank.  In my experience they're also very prone to worms.  Any fish going into the tank with them should also be quarantined and at least wormed before introducing them.  Even doing that, every single time I have added tankmates with my discus... they end up with a worm issue some time later and I end up needing to worm the whole tank again.

It's a good idea to have pure metronidazole and pure levamisole on hand.

Common discus tankmates are cardinal tetras, lemon tetras, rummynose tetras, bristlenose plecos, bosemani rainbows, german rams, and sterbai corydoras.  You can find some yahoo somewhere who's keeping goldfish, stingrays, and arrowana with them, but that doesn't mean it is the right thing for the fish, which I think is an important distinction.  

Edited April 5 by jwcarlson

[Tazalanche]

@jwcarlson nailed it. None of your current fish would thrive in a tank set up for discus, unless the cories are sterbai. Either the current fish couldn't handle the higher temperature long term or they would become discus food.

[madmark285]

In the USA, Discus are not cheap (~$50/fish). You may have a significant investment buying these guys.

So just adding to jwcarlson excellent post, keep the 15 gallon tank as a quarantine/hospital tank. I would not risk adding a new Discus directly into an established tank. What many do, keep a sponge filter going in your main tank and just use that when you need to setup the quarantine/hospital tank.

On 4/5/2024 at 8:04 AM, Cjbear087 said:

Because I can only have 1 tank,

That's what I told my wife, just one 75 gallon tank. When that tank started to leak, my solution was to buy a 40 gallon tank! And who can resist those PetCo aquarium sale, a 29 gallon tank is only $40 🙂

[Cjbear087]

On 4/6/2024 at 11:00 AM, madmark285 said:

In the USA, Discus are not cheap (~$50/fish). You may have a significant investment buying these guys.

So just adding to jwcarlson excellent post, keep the 15 gallon tank as a quarantine/hospital tank. I would not risk adding a new Discus directly into an established tank. What many do, keep a sponge filter going in your main tank and just use that when you need to setup the quarantine/hospital tank.

That's what I told my wife, just one 75 gallon tank. When that tank started to leak, my solution was to buy a 40 gallon tank! And who can resist those PetCo aquarium sale, a 29 gallon tank is only $40 🙂

In England, you can find 6cm discus for £25 - BUT I do agree with you that quarantining would be smart. If I bought an extra sponge filter and put it in my tank, would it cycle with my fx6 as long as I’m dosing ammonia and BB and waiting etc etc? Then once my tank is cycled I can just take the sponge filter out and put it in a quarantine tank? And it won’t crash my cycle in the main tank?

[madmark285]

On 4/6/2024 at 6:17 AM, Cjbear087 said:

And it won’t crash my cycle in the main tank?

You don't really need a quarantine tank when setting up a new tank, just put your initial fish purchase in the new tank.I would first get the new tank with the FX6 fully cycled before adding the sponge filter.

After a few weeks in a fully cycled tank, I would move the sponge filter to the 15 gallon tank then dose it with ammonia. I would also take a sponge out of the FX6 and squeeze all the crap into the 15 gallon tank. I am a big fan of ammonia in a bottle, you can test to verify the establishment of bacteria. 

So a question to the experts here at CARE. I now have a sponge filter with fully established bacteria colonies. When I move it back to the main tank, do I have to run an airline to it? I don't need it for filtration, my main filter is working great. My understanding, the bacteria in the non-running sponge filter may go dormant but will not die off. Once  supplied with ammonia/nitrite,  they will spring back to life and start multiplying. 

I ask this for my sump filters. When I break down my grow out/quarantine tank, I will move the sponge filter into the sump without an airline. 

Edited April 6 by madmark285