What happened?

[Hadesdrew]

BTW, I'm totally new to the fourms. Guy totally obsessed with saltwater fish told me to come here for anything and everything.
Well, I just had my african knifefish die(The bigger one in the tank that I've had longer, he was around 5") and I was kinda thinking he was a day ago because hes tail looked a lot different than normal, it was ghost white at the tip with missing fins then went pitch black an then kinda pinkish(This is all in a 1/2 inch). He was acting normal other wise. I home today and he was dead under the filter(Not stuck to it or anything) upside down. What made it so odd was he was completely white from his face to about 1 1/4th down and his tail white spot had spread about 1/4". I've had 2 knifes die before but they have never looked like this(Maybe cause they died of ich)but still I was wondering what happened to him. The other knife is 100% fine and shows no signs of fighting.
I'm starting to worry something might be in the tank because one of my mollies is hanging at the bottom and swaying a lot more than normal. And personally I don't want them to die.
Also, I had a 4th angelfish and it was white and pretty new. It can't fit in anythings mouth in my tank(It's like 5x bigger than the closest mouth size) so I'm wondering where did it go? I can't find it in the tank anywhere. I did move the decorations around yesterday so is it possible I burred him in there somewhere? He didn't get out of the tank already checked(It's totally covered so Idk how he would of anyway).

 

[Lupin]

to MFK!

I'd suggest answering questions below to cover all bases before we start looking deeper into this issue. This will save time speculating the issues.

1. What is the size of your tank?

2. What are your water parameters? State the brand of test kit used.

3. Is your aquarium set up freshwater or brackish water?

4. How long the aquarium has been set up?

5. What fish do you have? How many are in your tank? How big are they? How long have you had them?

6. Were the fish placed under quarantine period (minus the first batch from the point wherein the tank is ready to accommodate the inhabitants)?

7. What temperature is the tank water currently?

8. Are there live plants in the aquarium?

9. What filter are you using? State brand, maintenance routine and power capacity.

10. Any other equipment used (aside from heater and filter which are two very important components of the tank)?

11. Does your aquarium receive natural sunlight at any given part of the day? What is your lighting schedule (assuming you do not rely on sunlight for our viewing pleasure)?

12. When did you perform your last water change and how much water was changed? How often do you change your water? Do you vacuum the substrate?

13. What foods do you provide your fish? What is the feeding schedule?

14. What unusual signs have you observed in your fish?

15. Have you treated your fish ahead of diagnosis? If so, what treatments did you use? State your reasons for planning ahead of proper diagnosis.

16. Insert photos of fish in question and full tank shot if necessary.

 

[Hadesdrew]

1. What is the size of your tank?
55 gallon

2. What are your water parameters? State the brand of test kit used.
Well I normally get my water tested at petsmart, about every 3-5 days. They say everything is where it should be, low ammonia and such. Other than I have quite soft water and slightly low alkalinity levels.

3. Is your aquarium set up freshwater or brackish water?
Freshwater, small amounts of salt are added, very very small amounts.

4. How long the aquarium has been set up?
4 months

5. What fish do you have? How many are in your tank? How big are they? How long have you had them?
3 Otocinclus Catfish 1"(1 for 4 months, 2 for a month)
A Pictus Cat 3" 2 months
A spiny eel 6" 3 months
A golden dojo loach 4" 4 months
2 Rosy barbs 2 1/2"(I hate these guys so much, idk why) 3 1/2 months
2 African Knifes 5" 1 1/2 month (One of them died yesterday)
1 Male Paradise Gouramis 4" 2 months (Died this morning)(The other one in the video was moved out in a matter of a day just need to set up his tiny tank)
A Male Betta 3" 1 month (I can't find him so I'm assuming he is dead)
4 Angelfish 3" (3 of them 4 months, one of them, the one that died 1 week)
4 Mollies 3" W&D: 4 months B&Y:1 week (My white one died this morning, Yellow one died 3 days go, black one is totally fine, dalmatian one isn't doing too hot)
3 black skirt tetras 3" First fish so 4 months
A rainbow shark 5" 3 months

6. Were the fish placed under quarantine period (minus the first batch from the point wherein the tank is ready to accommodate the inhabitants)?
I don't have another tank really so I can't. So no.

7. What temperature is the tank water currently?
82 degrees

8. Are there live plants in the aquarium?
7 of them.

9. What filter are you using? State brand, maintenance routine and power capacity.
I have no idea what kind of filter but I'm using the one you get with the 55 gallon, top fin from petsmart.

10. Any other equipment used (aside from heater and filter which are two very important components of the tank)?
Do bubblers count? lol

11. Does your aquarium receive natural sunlight at any given part of the day? What is your lighting schedule (assuming you do not rely on sunlight for our viewing pleasure)? Very very little if any.
I normally turn off the light around 11pm, I have left it on the whole time for the last 3 days though...

12. When did you perform your last water change and how much water was changed? How often do you change your water? Do you vacuum the substrate?
A week ago and around 40%. Like once a month. Yes.

13. What foods do you provide your fish? What is the feeding schedule?
I feed them freeze dried brine shrimp or flakes 5 days out of the week and frozen blood worms the other two. I don't have a set day for any of them though.

14. What unusual signs have you observed in your fish?
Just a few hanging at the bottom more than normal and that white spot of the knifes tail.

15. Have you treated your fish ahead of diagnosis? If so, what treatments did you use? State your reasons for planning ahead of proper diagnosis.
I didn't know what it was so I didn't really do anything.

16. Insert photos of fish in question and full tank shot if necessary.
I have a video of the tank before anything bad happened. I did add a fake tree root thing from petsmart a few days ago(I put it in boiling water and all). That's about it. http://www.youtube.com/watch?v=4zkyffuegWk

 

[bob965]

I recommend getting your own test kit. "Everything is where it should be" is not specific enough. You should have zero ammonia not low ammonia. The first step to diagnosing any problem is knowing what your water parameters are.