Red Tailed Shark

[ric1984]

yeah, he ignores the other

no offence here mate but your tank sounds well over stocked. this could be a reason for the stressed shark.

however, the first thing i thought about was the electrical impulses the black knife fish gives off (i'm guess its a black ghost knife fish you have). everytime this fish moves, he or she is sending electrical waves out which bounce of objects and are sent back to him or her. this means these fish have extremely good vision although they're blind!
anyway, sharks are pretty sensitive to electrical impulses so having a fish like these together, you can imagine would cause a problem. i personally wouldn't mix these fish.

been fine, its just the last couple of days

 

[ALW]

The Black Knifefish will grow to large for that tank, could also be the culprit, a mix of both wont help either

 

[rabbut]

OK, there are three issues that are immediately obious to me while reading the thread, but only one would be likely to stress yoru shark at the moment.

Red tailed sharks need a minimum of 50 gals, 75 being preferable, as they are large active fish. He will be OK in a 70l at the moment, but when he gets to about 3 inches, it's time to move him on, or he will terrorise the other fish unless they are able to stand up for themselves. You get the odd nice one that won't but these only come about very rately

Stocking is the other issue that strikes me. The tank is very heavily stocked. 1 inch per gallon is recomended for beginners, and 2 inches per gallon for experienced hobbyists, whom are prepaired to put in additional work to maintain the tank. With 7l, you are loking at 13 inches as a beginner, or 26 if you are prepaired to do twice weekly 30% water changes, and have experienced the most common diseases
You currently have arround 50 inches of fish I have 13 years experince in the hobby, and I am not prepaired to even think about that kind of overstocking. To keep things "OK" you need to be doing one hell of a lot of mintanance, probibly including large daily water changes You need to lose some fish (preserably no literaly... ) Also, the Red tailed shark, and the knife fish will eat all other inhabitance later......Clearly an issue.
I have seen Knife fish at 18 inches, and I belive they can get bigger, so removing him and the Red tailed shark, whom are both innapropriate for a 13 gal tank would leave somwhere nearer 30 inches of adult fish, which is better, but still leaves you looking to loose more of your fish. I'd think about which of the other's you least like, as move them off while you are at it. Looks like a typical case of poor LFS avice

The final issue is that you don't have actual readings for water stats. I would be shoked if there wasn't readable ammonia and nitrite in your tank, and both are damaging to fish. The LFS often say the water is fine when they find these chemicals, as they think that they can sell you more fish if they do I've known LFS to say the water os fine, when ammonia reads 4mg/l, which would be fatal for many common community fish, so get them to give acctual numbers at the next test, don't take their word for it. Also, don't get them to test with strips, as they are as accurate as making random numbers up for water stats. Make sure they use liquid tests

All the best getting this sorted
Rabbut

 

[TigerLotus]

I second just about everything Rabbut said. The only disagree I would say is that the shark cant eat the fish (mouth is to small) but he will terrorize your fish to no end in that small of a tank, which is just going to cause more problems. IMO the reason for the loss of color is that the fish is stressed in such a small tank and is now unable to have a proper territory(s) now that he is pushing 3 inches as well as the picking on from other the fish.

I think that unless your upgrading to larger tank to accommodate the black knife, the black knife, rainbow shark, and angels all need to be re-homed. A 13 gallon tank is not suitable to any of those fish for any length of time other than something like QT or hospitalization.

Good Luck

Tiger Lotus : )

 

[ric1984]

I second just about everything Rabbut said. The only disagree I would say is that the shark cant eat the fish (mouth is to small) but he will terrorize your fish to no end in that small of a tank, which is just going to cause more problems. IMO the reason for the loss of color is that the fish is stressed in such a small tank and is now unable to have a proper territory(s) now that he is pushing 3 inches as well as the picking on from other the fish.

I think that unless your upgrading to larger tank to accommodate the black knife, the black knife, rainbow shark, and angels all need to be re-homed. A 13 gallon tank is not suitable to any of those fish for any length of time other than something like QT or hospitalization.

Good Luck

Tiger Lotus : )

Thanks for advice sorry its taken a while for me to get back to you

OK, there are three issues that are immediately obious to me while reading the thread, but only one would be likely to stress yoru shark at the moment.

Red tailed sharks need a minimum of 50 gals, 75 being preferable, as they are large active fish. He will be OK in a 70l at the moment, but when he gets to about 3 inches, it's time to move him on, or he will terrorise the other fish unless they are able to stand up for themselves. You get the odd nice one that won't but these only come about very rately

Stocking is the other issue that strikes me. The tank is very heavily stocked. 1 inch per gallon is recomended for beginners, and 2 inches per gallon for experienced hobbyists, whom are prepaired to put in additional work to maintain the tank. With 7l, you are loking at 13 inches as a beginner, or 26 if you are prepaired to do twice weekly 30% water changes, and have experienced the most common diseases
You currently have arround 50 inches of fish I have 13 years experince in the hobby, and I am not prepaired to even think about that kind of overstocking. To keep things "OK" you need to be doing one hell of a lot of mintanance, probibly including large daily water changes You need to lose some fish (preserably no literaly... ) Also, the Red tailed shark, and the knife fish will eat all other inhabitance later......Clearly an issue.
I have seen Knife fish at 18 inches, and I belive they can get bigger, so removing him and the Red tailed shark, whom are both innapropriate for a 13 gal tank would leave somwhere nearer 30 inches of adult fish, which is better, but still leaves you looking to loose more of your fish. I'd think about which of the other's you least like, as move them off while you are at it. Looks like a typical case of poor LFS avice

The final issue is that you don't have actual readings for water stats. I would be shoked if there wasn't readable ammonia and nitrite in your tank, and both are damaging to fish. The LFS often say the water is fine when they find these chemicals, as they think that they can sell you more fish if they do I've known LFS to say the water os fine, when ammonia reads 4mg/l, which would be fatal for many common community fish, so get them to give acctual numbers at the next test, don't take their word for it. Also, don't get them to test with strips, as they are as accurate as making random numbers up for water stats. Make sure they use liquid tests

All the best getting this sorted
Rabbut

Thanks for the advice, sorry its taken a while to get back to you

 

[markandhisfish]

We have had our Red Tailed Shark now for about 4 weeks, but the last couple of days his colour has reduced his red tail is not red anymore its gone a very light colour, also the black has faded too - he seems to be eating fine, the temp is ok and the water has been checked today and all was fine.

Could he be stressed ? i have noticed our Platti chasing him could that be the problem ??
Thanks

i am a relatively inexperienced aquarist but i have a red tailed black shark in my community tank and i have found that he likes to have a place that he can make his own . how is your tank set up? by this i mean plants rocks bogwood etc. i have dense areas of plants a large piece of bogwood a good size rock and a holow barrel. my red tail shark has set up home in 1 of the big plants and he defends it if any other fish come too close but other than that is a peacefull fish with good colours., so maybe all he needs is an area he can call his own territory. dont get me wrong i am not pretending to be an expert because i am far from it i am just sharing my admitedly limeted experience of this fish with you.
#

 

[ric1984]

We have had our Red Tailed Shark now for about 4 weeks, but the last couple of days his colour has reduced his red tail is not red anymore its gone a very light colour, also the black has faded too - he seems to be eating fine, the temp is ok and the water has been checked today and all was fine.

Could he be stressed ? i have noticed our Platti chasing him could that be the problem ??
Thanks

i am a relatively inexperienced aquarist but i have a red tailed black shark in my community tank and i have found that he likes to have a place that he can make his own . how is your tank set up? by this i mean plants rocks bogwood etc. i have dense areas of plants a large piece of bogwood a good size rock and a holow barrel. my red tail shark has set up home in 1 of the big plants and he defends it if any other fish come too close but other than that is a peacefull fish with good colours., so maybe all he needs is an area he can call his own territory. dont get me wrong i am not pretending to be an expert because i am far from it i am just sharing my admitedly limeted experience of this fish with you.
#

Thank you, we have got lots of hiding places, but our plec and black knife have them, so im going out to day so im going to get some more bits to see if that makes him a little happier. Thanks for advice