Angelfish Agression?

[Orge]

Hi,

I've just "inherrited" a stocked tank from a friend (so please excuse my ignorance). Generally, most of the fish seem fairly calm and happy, but there seems to be some agression between my Angelfish (prob Pterophyllum, not sure about gender) and a small shark (unknown species and gender). The angelfish is also slightly agressive with another similary sized fish (again, unknown species/gender...), but not as persistently. He/She is indifferent to the loaches (bigger) and smaller fish in the tank.

The agression consists of charging and nipping but, most of the time, I don't think he's actually making contact - it's obviously stressing both of them though. It looks like it might be territorial?

As far as I can tell, conditions in the tank are fine and there are no obvious problems with the fish. They have been moved quite a lot in the last couple of months (3-4 times) until settling at my place, but this behaviour has been apparent from the start. I'm not sure what to do, I do have a spare tank and filter, so I could seperate them but I would like to avoid this if possible.

Obviously pictures would be helpful, so I'll try to post some up later on this afternoon.

Any advice would be greatly appreciated.
Many thanks,

James

 

[DiscusKeeper403]

Well, it's most likely a problem due to territorial issues. How big is the tank? We will need to find out what the other fish you have. Sometimes community fish can't read the signals given off by the Angelfish. They posture to show that they are going to get aggressive and attack, but mainly only Cichlids can read this behavior.

 

[Orge]

Well, it's most likely a problem due to territorial issues. How big is the tank? We will need to find out what the other fish you have. Sometimes community fish can't read the signals given off by the Angelfish. They posture to show that they are going to get aggressive and attack, but mainly only Cichlids can read this behavior.

Thanks for the reply.

The tank is about 70L. I'm using a Hagen Biolife Filter and the lighting/lid unit from my tropiquarium 68 (this tank is at my parents). The substrate consists of small blue gravel balls and there are a couple of large bits of wood/stone with some smaller pieces. I'm feeding them a pinch of fish flakes 2-3 times per day. The temp is a constant 25-26 degrees (measured with a thermometer).

I've taken some snaps and will try to upload them tomorrow. There are a total of 9 fish in the tank. I've had a look through some online galleries and these are my best guesses at ID:

1 Angelfish (Black with a few silver patches)
1 Small Shark-like fish (~4 inches long, dark blue with a sort of "hammerhead" - possibly Giant Pangasius/Pangasius hypophthalmus)
2 Pleco (4-5 inches,3-4 inches) (Black/dark brown with yellow spots - possibly Adonis Pleco\Marbled Sailfin Pleco?)
1 Small Cory (leopard pattern - Leopard corydoras?)
2 Loaches (hide under the rocks most of the time):
1 is ~2-3 inches long, green/yellow with black/brown stripes - possibly Schistura similis?
1 is ~4-5 inces long orange/yelllow - possible weather/dojo loach?

2 unknowns:
1 is a small and goldfish-like
2nd is 2-3 inches long and silver with very long thin strands hanging from underneath.

The angelfish is agressive towards the pangasius and the 2nd unkown, but does not seem bothered by the others.

I'm sure I'm bound to be doing things wrong, as I've inherrited this tank with very little information/instructions - I don't even know who the original owner was!!?? Any help/advice is greatly appreciated.

Thanks,

James

 

[Straydum]

first of, your unknown shark, is probably an iridescent shark. it gets to a max of 4 feet. and i doubt your tank can hold it. second, you may want to try rearranging the deco in the tank, add some plants of there arent any. this should ease out the aggression abit. from what you said, your angel is only aggressive towards the pangasius and one other fish. if you took out the shark in the first place as mentioned above, things may change.

btw a 70 litre is around 15 gallons. your tank is SERIOUSLY OVER STOCKED.

 

[Orge]

first of, your unknown shark, is probably an iridescent shark. it gets to a max of 4 feet. and i doubt your tank can hold it. second, you may want to try rearranging the deco in the tank, add some plants of there arent any. this should ease out the aggression abit. from what you said, your angel is only aggressive towards the pangasius and one other fish. if you took out the shark in the first place as mentioned above, things may change.

btw a 70 litre is around 15 gallons. your tank is SERIOUSLY OVER STOCKED.

Ok. Having spoken to the previous keeoer, it seems that the tank was downsized after the original cracked - this was probably around 100l.
I think you're probably right about the shark ID, but how long does it take to grow to maturity? I don't know anyone who's going to be able to keep a fish that size, but it seems that will be a problem for the future rather than now - although I probably need to start thinking about it.

How many of these fish do you think my tank can support? I do have a second tank (I need to move/prep it though) and a friend has expressed interest in the Anhgelfish, so it may be possible to split them up. I guess I should be keeping an eye on the water chemistry?

Thanks very much for your advice.

James

 

[Straydum]

they have a rapid growth rate and reach sexual maturity and full size within 4 years. in a matter of months your shark would get almost half the size of your tank. one option is to return it to a local fish shop or give it to someone with a tank of around 250 gallons.

following the 1 inch per gallon rule, the 70L tank can only hold around 15 inches of MAX fish length. many of your fishes in there would easily outgrow this quota. unless you have a bigger tank, they would have to go to someone else. be it a friend or a shop. regarding the water, you should focus more on nitrates, ammonia and pH for now.

btw: "2nd is 2-3 inches long and silver with very long thin strands hanging from underneath"
i am guessing a gourami. the exact species i still cant figure it out.

 

[Orge]

they have a rapid growth rate and reach sexual maturity and full size within 4 years. in a matter of months your shark would get almost half the size of your tank. one option is to return it to a local fish shop or give it to someone with a tank of around 250 gallons.

Really?? My friend had the tank for about a year and I'm not aware that it's grown significantly. I've uploaded some pictures now, so it would be good to confirm the ID:

following the 1 inch per gallon rule, the 70L tank can only hold around 15 inches of MAX fish length. many of your fishes in there would easily outgrow this quota. unless you have a bigger tank, they would have to go to someone else. be it a friend or a shop. regarding the water, you should focus more on nitrates, ammonia and pH for now.

Ok, I'll look into relocating them or getting a second tank up and running. By the 1 inch rule, I should be able to support these fish between my two tanks, at their current sizes... Although it's still doesn't leave a huge amount of growth. Are there any others that are likely to grow significantly? Also, aside from the Angel Fish, would any particular split/combination be preferable?

btw: "2nd is 2-3 inches long and silver with very long thin strands hanging from underneath"
i am guessing a gourami. the exact species i still cant figure it out.

Here's a picture:

And for the remaining fish:
Larger Pleco (they're the same breed, but the other is an inch or two smaller)

Angel Fish

Leapord Cory

Unknown

Ive not managed to snap pics of the two loaches, as they're very elusive!

Many thanks for your advice, it's a pretty steep learning curve to inherrit a tank like this.

James

 

[DiscusKeeper403]

The ID shark (Pangasius hypophthalmus) will not grow, the tank is too small. I doubt it will live a whole lot longer, I feel bad because stunted fish live a life of agony. Max size is about 4 feet
HE NEEDS TO GO

The next fish is a Pearl Gourami (Trichogaster leeri), they can get aggresive and max out at about 4 inches, he should be out, but you need to consider the others first.


The other is a Bronze Cory (Corydora aeneus), he can stay in, but empty some of the other inhabitants, and get more of them.

 

[Orge]

The ID shark (Pangasius hypophthalmus) will not grow, the tank is too small. I doubt it will live a whole lot longer, I feel bad because stunted fish live a life of agony. Max size is about 4 feet
HE NEEDS TO GO

Ok, point taken. I'll give Sheffield Aquatics a ring tomorrow and see if they can take it. Please bear in mind that I inherited this tank (becuase they had nowhere else to go), and I'm doing my best - I genuinely have the interests of these fish at heart.

Thanks,

James

 

[DiscusKeeper403]

The ID shark (Pangasius hypophthalmus) will not grow, the tank is too small. I doubt it will live a whole lot longer, I feel bad because stunted fish live a life of agony. Max size is about 4 feet
HE NEEDS TO GO

Ok, point taken. I'll give Sheffield Aquatics a ring tomorrow and see if they can take it. Please bear in mind that I inherited this tank (becuase they had nowhere else to go), and I'm doing my best - I genuinely have the interests of these fish at heart.

Thanks,

James

I believe you! I am not pointing any fingers, nor am I trying to punish you. You are doing a good job, keep it up!

 

[molitor75]

I've had two pearl gourami for about 3 years and they are fine with the angels in my tank. However it is significantly larger at 260litres so I guess thats why there is no aggression.

 

[Orge]

Ok.
Out of the stock in my tank, I would most like to keep:

Angelfish
1-2 x Pleco (is it best to keep these as a pair? I'm not certain they particuarly like each other!!??)
Cory's

I'm not so attached to the Gourami/Loaches and the shark clearly has to go. Am I being realistic, or is this still too much for a 70l tank? I've contacted the local acquatics firm to find out whether they can help. Otherwise, I'll split them into a second tank or pass them on to a friend.
Thanks,

James

 

[Straydum]

someone correct me if i am wrong, but that pleco looks like a common pleco which gets up to a feet or so. if this it true, both plecos would have to go. you could replace the pleco with a bristlenose.

in my opinion,

1 angel,
1 bristlenose,
and a few cories

could be pushing the limit a little. is your tank heavily filtered?

 

[Orge]

someone correct me if i am wrong, but that pleco looks like a common pleco which gets up to a feet or so. if this it true, both plecos would have to go. you could replace the pleco with a bristlenose.

in my opinion,

1 angel,
1 bristlenose,
and a few cories

could be pushing the limit a little. is your tank heavily filtered?

Ok. I quite like the Pleco's, so I'm considering a larger tank. Assuming I streamline my stock as above, do you think it would be ok to upgrade the tank in a couple of months (to something in the region of 130-150 litres?)?

As for filtration, the tank has a Fluval Biofliter 35 from a Tropiquarium 68 (72l tanks). I cant find any specs, but I imagine that it is adequate rather than over specified.

Thanks,

James

 

[molitor75]

I would say that is still to small if they are common plecs. Ideally you would be looking at a 200+ litre tank just for those few.

I've had two pleco's before and found them to be rather territorial, not sure if two would be a good idea...

I have catfish and a pleco in my 240 litre tank and have a fluval 305 working in there. I've also got Gourami and Angels. They all seem to get on really well. Its been the same set up for over a year. However I do have lots of hiding places / quite places for them!