How Many Discus Can You Fit In A Tank?

[Charlyc11]

I was doing some research outside of Simply and came across the article in Macs Discus blog. I know that Mac has a reputation so I am not going to bash anybody I haven't deal with but I would like to see some input not about Macs Discus but this article (blog). This is kinda crazy specially the frequency of the water change never mind the amount of fish in the tanks. I have seen that large breeders do keep large quantities of fish per tank but their water change regimen is most likely way different from this article.

How Many Discus Fish Can I Put in a 100 or 55-Gallon Tank

I am asked this question often and before I give an answer, I always ask how often the person changes the water and cleans the tank. Getting the answer to this question is important for accurate feedback. Aquarium population and cleaning on a regular program will determine how many Discus fish can be safely added to an aquarium.

Discus fish belong to the freshwater South American cichlid family and therefore display a natural cichlid pecking order. I have found that adding more Discus fish to the tank calms their behavior by diluting this pecking order. If one cleans their tank and gravel once every 5 to 7 days on a regular basis, completes a 25% water change, and does not overfeed, you can stock a 100-gallon tank with 35 to 40 adult Discus fish. This stock level will result in your Discus fish growing evenly. There will be minimal pecking at feeding time and all the Discus fish will get their share of the meal. On the other hand, if one only wants to clean and change 25% of the tank water every month, then I would suggest following the one fish per 10-gallon rule and therefore stock with only 10 Discus fish. This stock level can lead to a severe pecking order resulting in uneven growth due to the dominant Discus fish getting all the food, growing faster, and eventually dominating the rest of the Discus fish in the tank. This is not good for your overall Discus fish community.

You can use the above formula to figure your comfort level and how much work you want to devote to aquarium maintenance and your particular tank size. For easy reference, if your setup is greater or less than 100-gallons you can do the math as follows.

150-gallon with once per week water changes Discus fish stock levels can be 55 to 60 adults, or once per month cleaning 15 adults.

55-gallons with once per week water changes Discus fish stock levels can be 15 to 18 adults, or once per month cleaning 5 to 6 adults.

30-gallons with weekly water changes Discus fish stock levels can be 6 to 7 adults, or once per month cleaning 2 to 3 adults.

The above formula is for Discus fish, any other varieties of small fish which are also in the tank do not count. Collectively the smaller fish will not put out a significant amount of waste.

[jeep]

That's why friends don't let friends buy from Mac's

[jwcarlson]

Written like a guy who cares about the first sale and the first sale only.

I could put 60 adult discus and 150 cardinal tetras in a 150 gallon tank and clean it once a week.

[Iminit]

I remember when Macs discus was a well known seller. His high fin blues were really nice looking discus. Of course he’s probably sold the name and this is just a seller. 60 discus! Wow and why? Funny though a few years back you did see lots of pictures of people who bought into this. Many way over stocked tanks. Don’t see it much anymore though. Live and learn I guess. Funny what people just outright believe. But yes I remember the pictures of Macs fish in the back pages of TFH.

[CliffsDiscus]

Macs had those Emerald Green Discus at the same time Fairly Lake Discus(Herman Chan)had the Emeralds too.

[brewmaster15]

Like all things crazy, there is often a nugget of truth in it. You can keep 35 adult Discus in 125 gal tank. I know this as fact. lol. However, the tank has to have excellent filtration . Weekly water changes of 25% is not going to cut it at all . Daily large water changes are needed. And yes, he is correct that it will get rid of the aggression. The tank he is describing is a hatchery tank.,,,not a hobbyist tank. There is no joy in watching 35 Adult Discus in a 100 gal tank. Theres little room to move...so the behavior is boring. Also the term adult is misleading. 5" fish can be adults 7.5 " take up much more room and put out more waste.

Cramming juveniles together and growing out with daily 100 % wc or drip systems can allow for over stocking and and can improve growth because they enter feeding frenzies... and theres no room for Bullies.

The flaws with the advice on these stocking levels is dangerous.. It will always be far better for Hobbyists to understock a tank and enjoy the fish naturally interacting than overstock and crowd the fish under conditions were you have reduced them to commercial livestock.

Just because you "can" do a thing, does not mean you should.


al

[Charlyc11]

So to the chase, how long can I keep the juveniles in the 29 gallon tank? I will move them to a 75 gallon next and then after offer to the members if they are of good stock but first I need cull the undesirables with some input from the forum. I will post lots of pictures in their threads. The one 29 has about 120 and the other about 50. So far one death from I could see I am sure the parents took care of some in the beginning. I will start taking some more picture I have a new Iphone 15 pro Max that need some trying out.

[brewmaster15]

Chuck how much water can you change?

[Charlyc11]

Chuck how much water can you change?

I been doing 50% a day and could go to 70% if needed.

[brewmaster15]

Chuck with those numbers of fry I would try and do more. If you don't you risk shape and skeletal issues..

[brewmaster15]

Take some pics when you can.. I would start culling poor growers as soon as possible.

[Charlyc11]

I can't tell how they are going to turn out and the pictures don't do them justice.

https://photos.app.goo.gl/6wanWCfqFcpryCeB9

[For100]

That's why friends don't let friends buy from Mac's

You crack me up! This is so funny.

[brewmaster15]

I can't tell how they are going to turn out and the pictures don't do them justice.

https://photos.app.goo.gl/6wanWCfqFcpryCeB9

Chuck most of the fish look like they are growing very well. I noted a few things you should cull for..

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2024-04-16_19-58-24-398.jpg

2024-04-16_20-08-36-708.jpg

Al

[Charlyc11]

I will do that thanks for the input Al always appreciated.

I guess I have some work cut out for me.