Newbie who needs advice!

About a month ago purchased my first fish tank ever! Always wanted one and finally after years of contemplating bought a 240L tank. Did all the right things stocked with live plants and ornaments. Beautiful! Anyway got to purchasing my first fish. We bought a black ghost knife fish (i know what you're thinking) and a rainbow shark. A couple of weeks later I purchased 2 discus and a catfish. I was stoked...until today. I woke up to a dead discus and I'm concerned the other one will die too. The other 3 are thriving. The BGK feeds from my hand...all seem content. The discus is feeding almost out of my hand..not quite but almost. I've checked my ph levels and nitrate which all are stable and haven't changed. Does anyone know much about discus? It happened after I did my water change 2 days ago...26 degree temp...such beautiful fish and would love more just want to make sure I have everything right

Sad to say discus are incredibly difficult fish to keep for anyone. They require specific ph no higher than 6,5, water temp at least 28°C. They are also schooling fish to be kept in at least number of 6.
Due to these conditions, they are not good community fish, since the other fish will not tolerate these temperatures.

Please specify your tank dimensions, ph, kh, temp and numbers of the other species
Thanks

Okay I am super new to this so please no judgement. I have had discussions with an aquarium expert who has been super honest from the get go since I purchased my tank but wasn't there for my purchase of my discus. Including the 2 discus I had there were 5 fish in total in a 240l tank. As mentioned above the fish. Ph I have been told is high at 7.6 but worried about changing it and causing more upset as the rest of the fish are fine. Nitrate is 0 and temp is 26 degrees. Only 1 of each species now so only 4 fish did a 25% change on Sunday and added 1 cap of conditioner as directed water straight from the tap all fish are fine but this 1 discus i woke up to dead this morning. Would love more but want to know what I am doing wrong..

I'm limited to the fish because of my BGK but I love him/her and will work around it.

Ok, what I would do in your situation, is try to rehome the remaining discuss to someone who has them, because in this condition, it will not survive long.

You should focus the tank around the BGK then. It is a large fish, requires lots of wood, stones, high flow, good water quality. Temp would be best 25°C. You should have several tubes, for this fish to hide, because some of them will be occupied by the catfish.
I hope you have a sandy substrate.
The fish is fully nocturnal, so you should have nothing that disturbs it during the day too much.
Rainbow shark is listed as not compatible tankmate for the BGK, so if you are serious about it, rehome it as well.
If it were me, I would rehome the catfish as well, but that is only because it occupies the same hiding space and I am not sure how that will work.

You should focus on getting the tank done for the BGK, keeping this for a while as a solitary fish. Once you establish the water quality and good feeding, you can do some research about tankmates

Beastije said:

Ok, what I would do in your situation, is try to rehome the remaining discuss to someone who has them, because in this condition, it will not survive long.

You should focus the tank around the BGK then. It is a large fish, requires lots of wood, stones, high flow, good water quality. Temp would be best 25°C. You should have several tubes, for this fish to hide, because some of them will be occupied by the catfish.
I hope you have a sandy substrate.
The fish is fully nocturnal, so you should have nothing that disturbs it during the day too much.
Rainbow shark is listed as not compatible tankmate for the BGK, so if you are serious about it, rehome it as well.
If it were me, I would rehome the catfish as well, but that is only because it occupies the same hiding space and I am not sure how that will work.

You should focus on getting the tank done for the BGK, keeping this for a while as a solitary fish. Once you establish the water quality and good feeding, you can do some research about tankmates

Click to expand...

Appreciate the feedback. At this stage they all get along really well. When you say in this condition..do you mean my discus being solo? I have a gravel substrate but doesn't appear to be an issue as it hides in its castle. Catfish does hide in the same space as the BGK but getting more spaces for them this weekend. My main question being is my water affecting the discus? They were fine and cruising until last night.

Pictures or video of the fish?
What are your exact water parameters? (Ammonia, nitrite, ect)

There are some major issues with the stocking that need to be addressed urgently.

Your aquarium is a 240 litre that has been running around 1 month.

Firstly did you fully cycle the aquarium before adding the fish?
What is your maintenance routine each week?
Please post a full frontal view photo of the aquarium.

BGK....minimum requirement is 400 litre aquarium, they grow to around 50cm long. Temp 24-26 and an external filter with UV is recommended due to the waste products and the fish being extremely sensitive to water chemistry imbalance. Max pH is said to be 8 so your pH is on the high end. They are nocturnal predatory.

Discus....your aquarium is bare minimum for 4 fish, 20 litres per fish is the average. Temp 28-30 and external filter with or without sump is preferable, like the BGK they are very sensitive to water chemistry imbalance. Max pH is around the 6.8, yours is way too high.

Rainbow Shark.....again the aquarium is bare minimum for one fish, they grow to around 15 cm. Temp 24-27 degrees. Should not be sharing space with bottom dweller fish such as catfish as they are potentially aggressive. Again they are sensitive to water chemistry imbalance and your pH is on the high end of their spectrum.

Please confirm type of catfish as they can usually require different conditions.

Whoever suggested the mix of fish really was not doing you any favours, all the fish are non beginner fish, all require specific conditions to thrive that as things stand are not being met.

Sorry to burst the bubble but I never sugarcoat things, the "expert" who sold these fish to you saw their sales commission and not your ability to care or look after fish properly.

I keep hearing this. At this stage I have a planted tank with ornaments all fish get on well and looking at getting a larger fish tank in time. They are all babies at this point the only issue is the discus. Nitrate is 0,,,ph is 7.6nwhich is high for discus I have now been told although they have been fine until the water change...26 degree temp...my discus were getting beautiful in colour no signs of stress until last night al, other fish are feeding well and acting normal...my main question is my ph levels I am aware are high but have always been stable...do I drop the ph to cause stress or just monitor. Do I add more discus but based in the information which is very mixed...I'm not leaning this way. I'm on this forum for advice...my other fish in my eyes are great wandering and feeding well. BGK is eating from my hand which is a major achievement for me but I'm sad one of my discus passed and don't want this to be an ongoing issue. I'm not a pro..I need lamens terms...yes or no to discus in my tank with the fish I currently have. Do I increase to make it feel secure maybe being the reason OR avoid

Hi and welcome to the forum

At this stage do not add any more fish of any type. We need to work out what is going on and when we know, then we can see about adding more fish.

-------------------------
A pH of 7.6 should not kill discus unless they were kept in acid water (pH below 7.0) at the shop.

If you can contact the shop, ask them what the pH and GH of their discus tanks are (in numbers) and find out what the GH is measured in (eg: ppm, dGH, or something else).

-------------------------
A temperature of 26C is fine. It's at the bottom end for discus but you can raise it if needed. Right now you don't need to raise it. If you do want to raise the temperature, take it up to 27 or 28C, but I wouldn't bother at this stage.

-------------------------
There are 3 parts to a filter cycle. Ammonia is produced by fish food and waste breaking down in the water. This is eaten by good bacteria and converted into nitrite. The nitrite is eaten by different bacteria and converted into nitrate. You get rid of nitrates by doing water changes.

If the filter has not developed the colonies of good bacteria, you could have an ammonia or nitrite reading and these can kill fish.

You have mentioned nitrate but ammonia and nitrite are much more important.

If you have a test kit for ammonia and nitrite, then check the water for them and post the results in numbers here.

-------------------------
A possible cause of death is the tap water.

Do you know if there is chlorine or chloramine in the water?
If you contact your water supply company by phone or check their website, you should be able to find out if you have chlorine or chloramine in the water. Chlorine is easy to get rid of but chloramine is more difficult.

If you are in Perth, WA, you have chlorine but I don't know about the other states.

If you fill a clean bucket with tap water and add the required amount of dechlorinator, then aerate the mixture for 30 minutes, it should remove any chlorine or chloramine from the water. This should make it safe for the fish.

Any new water should be free of chlorine/ chloamine before it's added to the tank.

When you contact the water company, you can ask them what the GH (general hardness) and KH (carbonate hardness) is. Find out what they are measured in too.

If you have soft water, you can add some peat to a bucket of tap water and it will drop the pH. When the pH is around 6.8-7.0, you can use that water for water changes. This will slowly bring the pH down in the tank and reduce any pH issues affecting the fish.

-------------------------
If you can post some pictures of the fish, we can check them for diseases.

Please don't take this the wrong way, but @wasmewasntit has a point about whoever sold you the fish, they didn't do you any favours at all. I would never sell a beginner fish keeper, discus or a black ghost knife fish. You might want to look around and visit a few other pet shops in your area and see if they are willing to sell you discus. Don't buy any, just go into the shop and say "I'm new to fish keeping and like discus, can I keep them as my first fish?" If the shop says yes, have a look around but don't buy anything, and maybe find somewhere else to get your fish. No shop should be selling discus to beginners.

-------------------------
Make sure you don't have any cream, soap, perfume, hand sanitiser, or anythign else on your hands/ arms when working in the tank or feeding the fish. These substances can leave residue on your skin that can wash off n the aquarium water and poison the fish.

Chiara2707 said:

I keep hearing this. At this stage I have a planted tank with ornaments all fish get on well and looking at getting a larger fish tank in time. They are all babies at this point the only issue is the discus. Nitrate is 0,,,ph is 7.6nwhich is high for discus I have now been told although they have been fine until the water change...26 degree temp...my discus were getting beautiful in colour no signs of stress until last night al, other fish are feeding well and acting normal...my main question is my ph levels I am aware are high but have always been stable...do I drop the ph to cause stress or just monitor. Do I add more discus but based in the information which is very mixed...I'm not leaning this way. I'm on this forum for advice...my other fish in my eyes are great wandering and feeding well. BGK is eating from my hand which is a major achievement for me but I'm sad one of my discus passed and don't want this to be an ongoing issue. I'm not a pro..I need lamens terms...yes or no to discus in my tank with the fish I currently have. Do I increase to make it feel secure maybe being the reason OR avoid

Click to expand...

Have you considered that maybe you keep hearing it/getting told that because it’s true? I’m not trying to be rude or sarcastic, I’m genuinely curious. We’re trying to help with what we can, and your stocking is a problem

Hi and welcome to TFF...
Well, as already been told, discus fish need softer water than what you have right now. And mind that discus fish are very sensitive fish to keep. Especially when they get bigger. In my own experience, the turquoise discus fish is one of the stronger discus fish there is.

I completely understand. As I've said I am a newbie so this is all a learning curve for me and I am trying to do what's best for the fish. I do have the turquoise discus it appears..dont know if this makes a difference. I have been told it's not until they get older their colours start to become more prominent? Seems okay this morning. Am I right to be feeding them a mixture or blood worms and pellets? Although they are floating pellets that I was given and they don't seem to go for them which concerns me that they may not be getting the mixed diet they need but they of course love the blood worms. Here is the discus...it seems to be different colours on one side to the other...I will get the kid for the ammonia and nitrite this weekend. I've only got the kits for the ph and nitrate at the moment.

The fish looks fine from a disease perspective, however it does have a bit of excess mucous on its tail. This is most likely from ammonia or nitrite in the water.

Feed the fish a varied diet that includes dry flake or pellet foods, frozen foods like brineshrimp, bloodworms, prawn, fish, marine mix, and live foods like brineshrimp, daphnia, small earthworms, mozzie larvae, etc.

How can you tell it has excess mucus? Just so I know what to look out for. Will do a big food shop this weekend for them lol am I right in saying bloodworms are too high in protein and should only to be fed this a couple of times a week? I've read of people feeding pretty much only that with no issues so as you can see so much information and some really conflicting. What is right and what's wrong?