Name that fish?

Hi all - my first post, and a quick query if you don't mind?

Here's a slightly low quality photo of two fish my 10 year old son caught at a
local (Uk) pond.

http://homepage.ntlworld.com/paul.dunn4/DSC00572.JPG

"Hey dad, can we keep them? Pleeeeeeease!"

I think they're perch - they have a spiny dorsal fin that is raised from time to
time. I don't mind keeping them - hell, we keep every other damn bug and beetle
he comes home with, and he's got a very impressive ecology going in a larger
tank consisting of water scorpions, dragon fly nymphs (which he has managed to
get adult dragonflys from) and other crawlies which has been going strong over a
year now. If they're perch then they're gonna get a whole lot larger and will
need a much bigger tank, but that's all I had available at the time.

Question is, what do I feed them? I can pop out to the petshop in the morning,
but I need to know what to buy. They're not aggressive though they do attack the
pond snail by smacking it with their tails from time to time (my son said they
did this to his net). I can hardly put them in with his bug tank, as they'll
likely eat everything in sight, yes?

Plus I think they're rather attractive with their striking stripes (which change
intensity all the time) and red fins.

Anyone any help?

Thanks!

"Dunny" wrote in
:

http://homepage.ntlworld.com/paul.dunn4/DSC00572.JPG

Yes, perch. ("Common European perch" to the folks on the other side of the
Atlantic.) Pretty but gets rather large and needs good quality of water.
Predators, eat everything which moves including fish smaller than
themselves. Not one of the easiest wild fish to start with, as perch needs
room and doesn't like warm water all year round. It might be best if your
son would release these ones and catch something easier to take care of,
like roaches. They do much better in room temperature year round and
survive on flake food. Although that small container is far too small for
them too. Best way to get fish is to buy a decent aquarium first and catch
the fish only after that. Good size for roach and its relatives is 200
liters (50 gallons) or bigger.

Liisa

In ,
Liisa Sarakontu typed:
"Dunny" wrote in
:

http://homepage.ntlworld.com/paul.dunn4/DSC00572.JPG

Yes, perch. ("Common European perch" to the folks on the other side
of the Atlantic.) Pretty but gets rather large and needs good quality
of water.

I noticed - to our dismay, one of the perch has passed away (to be buried in the
garden under a seashell tombstone, which I suppose if nothing else teaches my
son some important lessons in something or other) but the other one is doing
reasonably well. It's still flashing around the tank after spiders and other
bugs, but does spend some time swimming at the surface gulping. It shouldn't be
a lack of oxygen as the water is 1 day old, but it may be an attempt to cool
off - when I added a good mugful of cold water it stopped and became much more
lively.

It might be best if your son would release these ones and catch
something easier to take care of, like roaches.

We're taking the perch back tonight - and I've promised he can keep a couple of
wild fish when we have somewhere better to keep them. He has looked after a few
goldfish and other more exotic fish quite well in his own tank, so I think he'll
do well with the right fish.

Perch was probably the wrong choice come to think of it, but they're a tad
easier to catch Any tips on getting the others (which I presume to be
roaches) with a garish green net and a bucket? :-)

Thanks for the advice,

Paul.

"Dunny" wrote in
:

I noticed - to our dismay, one of the perch has passed away (to be
buried in the garden under a seashell tombstone, which I suppose if
nothing else teaches my son some important lessons in something or
other) but the other one is doing reasonably well. It's still flashing
around the tank after spiders and other bugs, but does spend some time
swimming at the surface gulping. It shouldn't be a lack of oxygen as
the water is 1 day old, but it may be an attempt to cool off - when I
added a good mugful of cold water it stopped and became much more
lively.

If you don't have any decent filtration there, it most probably is
suffering from lack of oxygen and it might have killed the other fish. Only
a handful of fish species survive without any water movement (which is the
main way to add oxygen to water). The warmer the water is, the less oxygen
it can hold.

He has
looked after a few goldfish and other more exotic fish quite well in
his own tank, so I think he'll do well with the right fish.

Your son doesn't sound very old, and you mention the goldfish in a way
which makes me think that you don't have them any more. So I don't think
that they were taken care "quite well", as well cared for goldfish live
easily up to 20 years, even over 30 years. Yep, much longer than a dog or
cat.

Goldfish with natural body form grow over 30 cm long, and the deformed ones
can grow up to 15-20 cm plus tail. They are very hardy, and often survive
months, even years in those horrible little bowls but they really are
suitable only for ponds or big aquariums, 300 liters and up. They are also
schooling fish, and you actually need something like 800 liters to house
properly six 30 cm long fish.

"Real exotics", real tropical fish like neon tetras are actually much
better fish for a beginner in this hobby. Much better suited to live in
room temperature year round and stay small enough to be happy in a rather
small tank.

Perch was probably the wrong choice come to think of it, but they're a
tad easier to catch Any tips on getting the others (which I presume
to be roaches) with a garish green net and a bucket? :-)

Bigger net. But also think of buying the fish instead of catching your own.
Many tropicals are much easier to keep than natives due to room
temperature. Many species have also been bred in captivity for fish
generations and the result is often nicely adapted to typical tap water -
especially if you can find fish which are bred close to where you live.

Liisa

In ,
Liisa Sarakontu typed:

He has
looked after a few goldfish and other more exotic fish quite well in
his own tank, so I think he'll do well with the right fish.

Your son doesn't sound very old, and you mention the goldfish in a way
which makes me think that you don't have them any more. So I don't
think that they were taken care "quite well", as well cared for
goldfish live easily up to 20 years, even over 30 years. Yep, much
longer than a dog or cat.

I wonder what makes you say that? He's had them, and cared for them, with no
deaths for about 5 years now which is why the Perch has thrown him a bit. And
he's been solely responsible for them (except when on holidays). He's also
responsible for a three year old dog, and an X year old rescue cat... Though
they don't live in a large tank in his room

Goldfish with natural body form grow over 30 cm long, and the
deformed ones can grow up to 15-20 cm plus tail. They are very hardy,
and often survive months, even years in those horrible little bowls
but they really are suitable only for ponds or big aquariums, 300
liters and up. They are also schooling fish, and you actually need
something like 800 liters to house properly six 30 cm long fish.

His tank is about 40 litres, I think, and contains 4 fish - one loach, two
goldfish and one Zebra Danio (sp?). They seem to thrive ok, but the loach eats
all the plants in sight. No matter - he spends pocket money on replacement stuff
for the tank every week.

Bigger net. But also think of buying the fish instead of catching
your own. Many tropicals are much easier to keep than natives due to
room temperature. Many species have also been bred in captivity for
fish generations and the result is often nicely adapted to typical
tap water - especially if you can find fish which are bred close to
where you live.

I'll take that on board, and thanks!

Paul.

On Mon, 23 Aug 2004 16:20:42 +0100, "Dunny"
wrote:

reasonably well. It's still flashing around the tank after spiders and other
bugs, but does spend some time swimming at the surface gulping. It shouldn't be
a lack of oxygen as the water is 1 day old, but it may be an attempt to cool
off - when I added a good mugful of cold water it stopped and became much more
lively.

The temperature isn't an issue, unless the water is over 27 celsius or
so. My guess is that you're seeing the effects of nitrite poisoning,
especially considering how small the aquarium is. More and bigger
water changes should fix it.

Perch was probably the wrong choice come to think of it, but they're a tad
easier to catch Any tips on getting the others (which I presume to be
roaches) with a garish green net and a bucket? :-)

IMHO roach is more sensitive than perch.

Rudd (Carassius carassius) is an ideal choice. It's a close relative
of the goldfish, just even more indestructible. Other good natives for
aquaria is ruffe (Gymnocephalus cernuus), a smaller and less rapacious
version of perch; and Stickleback (Pungitius pungitius & Gasterosteus
aculeatus), basically bullet-proof fish with interesting breeding
behaviour.

"Dunny" wrote in
:

His tank is about 40 litres, I think, and contains 4 fish - one loach,
two goldfish and one Zebra Danio (sp?). They seem to thrive ok, but the

Please find out (or ask your son to find out) what each fish species you
have really needs. Goldfish need ROOM, they get badly stunted in small
tanks. Zebra danios are schooling fish which shouldn't be kept alone. There
are few dozen species of loaches, and many of them need much warmer water
than goldfish or danios. Many o fthem are schooling too, and get too big
for these liters.

Liisa

In ,
Liisa Sarakontu typed:
"Dunny" wrote in
:

His tank is about 40 litres, I think, and contains 4 fish - one
loach, two goldfish and one Zebra Danio (sp?). They seem to thrive
ok, but the

Please find out (or ask your son to find out) what each fish species
you have really needs. Goldfish need ROOM, they get badly stunted in
small tanks. Zebra danios are schooling fish which shouldn't be kept
alone. There are few dozen species of loaches, and many of them need
much warmer water than goldfish or danios. Many o fthem are schooling
too, and get too big for these liters.

Thanks - it'll be a joint effort, I think between him and myself

We're going to have a look round at the library for some books and sort out a
decent size tank at the weekend. Thanks for the advice.

BTW, the remaining Perch went back to the pond yesterday - my son is quite
chuffed that he did "the right thing".

D.

In ,
Mean_Chlorine typed:
On Mon, 23 Aug 2004 16:20:42 +0100, "Dunny"
wrote:

reasonably well. It's still flashing around the tank after spiders
and other bugs, but does spend some time swimming at the surface
gulping. It shouldn't be a lack of oxygen as the water is 1 day
old, but it may be an attempt to cool off - when I added a good
mugful of cold water it stopped and became much more lively.

The temperature isn't an issue, unless the water is over 27 celsius or
so. My guess is that you're seeing the effects of nitrite poisoning,
especially considering how small the aquarium is. More and bigger
water changes should fix it.

Which would probably explain the sudden release from lethargy when I changed the
water. I did that (about two thirds of the water gone replaced with water from a
bucket that was half tap water and half pond water, which had stood outdoors for
about 24 hours) about four times before the perch was released. The tank now has
just bugs and stuff in it (and an impressively large Great Pond Snail) which are
doing very well. Some of the bugs are breeding - I kind of take that as a good
sign, as from a purely medical perspective (which is the greater part of my
career and training) is _usually_ found only when the environment is relatively
safe and energy availability is sufficient.

The tank is certainly not appropriate for fish, but insects seem to thrive...

IMHO roach is more sensitive than perch.

We'll skip those then

Rudd (Carassius carassius) is an ideal choice. It's a close relative
of the goldfish, just even more indestructible. Other good natives for
aquaria is ruffe (Gymnocephalus cernuus), a smaller and less rapacious
version of perch; and Stickleback (Pungitius pungitius & Gasterosteus
aculeatus), basically bullet-proof fish with interesting breeding
behaviour.

Interesting - what kind of tank (and contents - water/environment) would you
recommend for say, two stickleback? There are many ponds within walking
distance, and one contains quite a large stickleback population - I think
they're carnivorous, there's nothing else living there. Correct?

D.