Young Flounder: Behavior Change + Diet Question

[simonero]

I have a couple questions about what, according to a post I just read, is probably a hogchoker flounder.  I have completely given up asking my local fish store - I gather they know nearly nothing about a single fish they've sold me this far.  My fish is between 1/2in and 1in and I've had it slightly over a week I believe.
 
First question - What does this fish need to eat?  Now, and when it matures slightly.  The kids at the fish store said my Spectrum Small Fish Formula was fine and seemed uninformed that the internet says everywhere that I need live food.  Despite appearances and evidence otherwise... is it possibly eating, is this fine for now, and what should I eventually be feeding it?  
 
Second - His behavior changed drastically today.  Before he was all alone when I got home tonight (been having major new tank and mortality issues..), he always stuck to the side near the rocks, fluttered around sneakily for short periods of time, disguised and did his thing discretely.  ONCE I saw him near the top.  Ever since I got home and he's now the sole survivor (ha ha) he's been hanging out on the top.  Only.  When I tapped him thinking he was dead, he plummeted to the depths briefly.  Otherwise he's been on the top two hours, occasionally doing the worm and drifting slowly.  Is this OK?
 
I'd appreciate any input about these things, and in general info going forward with my flounder.  I'd really like to do everything I can to keep this buddy alive and don't know a thing =(

 

[TooManyChoices]

What are your water parameters? pH? Ammonia? Nitrite? Nitrate? Hardness? They're the really important ones. What size tank is it in?

As far as feeding it'll probably take blood worm, live would be best but frozen might suffice. Eventually other meaty foods, small bits of fish, prawn, etc. It MIGHT eventually take dried foods.

 

[simonero]

10gallon tank.  pH is slightly below 7 as of yesterday.  (Going to look into a testing kit).  LFS says no ammonia but per my discussions in another thread, they are probably just straight up wrong because everything else kept dying.  I'm probably 5 days in to the cycle I have since my last full water change, to give you an idea of where the rest *might* be at.
 
I don't think I know about the concept of hardness yet.  I'll try to look it up again but what do I need to know to answer that question?
 
Can I get that food at the LFS?  Do I need to do anything to it besides dropping it in there?  I have a feeling the LFS won't be able to tell me the best thing to do for a flounder - they didn't even know it ate live food..

 

[simonero]

What are your water parameters? pH? Ammonia? Nitrite? Nitrate? Hardness? They're the really important ones. What size tank is it in?

As far as feeding it'll probably take blood worm, live would be best but frozen might suffice. Eventually other meaty foods, small bits of fish, prawn, etc. It MIGHT eventually take dried foods.

 
Just realized I might need to quote you for you to know I responded.  If not sorry - new to forums in general!

 

[TooManyChoices]

Okay. I'm not too familiar with that fish but I would think pH definately above 7.

Chances are your ammonia is high. That will causes deaths. DON'T DO FULL WATER CHANGES! 50% maximum whilst the tank isn't stable. Don't touch your filter either. That houses good bacteria.

Research AQUARIUM NITROGEN CYCLE. And buy a test kit!

Foods should be easily purchased from lfs, start with blood worm, put a few in and if they to uneaten remove immediately.

It's hard to advise as we really need to know what the water parameters are.

Also 10 gallon will be insufficient in the long run.
Also

 

[MBOU]

More to the point, what salinity is the water?
 
Do you realise that despite being named as a 'freshwater' fish, all this means is that it is not a true marine fish. They are, however.. a brackish water fish that moves to fully marine as it gets older like many species.
 
They also get about 20cm long and are predatory.
 

This species should not be kept in freshwater despite it’s name. As specimens get older it’s better to keep them in marine water. Trinectes maculates (hogchoker, freshwater flounder) is best kept with a substrate made out of fine grained sand that allows them to burrow. A larger grained substrate can hurt this species.

 
I would suggest that the water quality is likely not so great (what are ammonia, nitrite and nitrate levels?) and that without salt in the water, the density is not right for the fish.

 

[simonero]

Foods should be easily purchased from lfs, start with blood worm, put a few in and if they to uneaten remove immediately.

 
I fed him some live blackworms (they didn't have blood worms but the guy said it was OK?).  Flounder appears entirely disinterested.  I was told it was ok for me to leave them in the tank though because they are alive.  Thoughts?
 
Yes I'm aware he's brackish and I'll eventually have to get rid of him... I just wasn't when I bought him.  And I'm very attached.  Once he gets big enough that he doesn't seem so fragile, I'm going to start considering my options.  I have no salt in my water as of now because I'd like to add freshwater fish into it once it cycles fully.
 
I got my water tested tonight and they said pH was 7 and the other levels were all perfect.  He's continued with the different behavior, but I've noticed he's way more likely to chill on the surface at night.  Maybe this behavior just seems odd because usually they don't have the whole tank to themselves and no sand?  (if he stays alive through the next like week or so I'm going to buy something more sand-like to add in for him)

 

[MBOU]

Well... he isn't likely to stay alive long if you dont put some salt in there.... salt in the water changes the density of the water and might effect how he is swimming.
 
You also dont know what your water parameters are, tbh its likely that your ph is too low (though id have to double check that) but in brackish tanks it will likely be higher. Its hard to know what results are 'perfect' because ideal paramters are different for each species and seeing as you are keeping a brackish fish in freshwater and its showing signs of not being well, they clearly arent 'perfect'.

 

[the_lock_man]

Okay. I'm not too familiar with that fish but I would think pH definately above 7.
 

 
"Would think" isn't good advice, if you don't know, then please don't advise.
 
 

Chances are your ammonia is high. That will causes deaths. ......... Don't touch your filter either. That houses good bacteria.

Research AQUARIUM NITROGEN CYCLE. And buy a test kit!

 

 
Wouldn't disagree with any of this advice.
 
 
 

 DON'T DO FULL WATER CHANGES! 50% maximum whilst the tank isn't stable.
 

 
IMHO, this is not good advice. If you have a tank with high ammonia, indeed anything over 0.5ppm, you need to do greater than 50% water changes to get the ammonia into a relatively safe area. There is no problem with carrying out water changes of this magnitude, so long as the temperature of the water is reasonably well matched, and has been dechlorinated.

 

[simonero]

I am considering adding some salt to the tank...
 
I don't know if he ate it actually but he definitely nipped at one of the blackworms I pur practically on top of him after a bit, so I'm hoping that's a good sign.
 
If I'm going to be making the water slightly bracking, any advice?  I don't know a thing about doing it, which is why I was hesitant, but I suppose I do need to move forward and accept that there's still a million things to do to my tank to make it fully flounder friendly.  My friend mentioned he could give me some supplements or something, but I haven't discussed any details and have no idea how much my tank would need, or when I would need to start increasing the salt levels even more.

 

[MBOU]

Best bet would be to make a post in the Brackish section, the most knowledgeable person is Neale Monks. But I believe if you search in that section, there have been a few posts about flounders before. Certainly there will be information on going brackish! Its not too difficult!! You just need a few things. For starters... patience... and other than that... a refractometer to check salt levels (hydrometers arent precise at all and certainly not in brackish) and you will need some marine salt (stuff used in marine tanks, not tonic salt or anything).
 
It will be a case of very very gradual increases, you might find it helps his appetite too!

 

[DerpPH]

They also take clams and other shellfish once they get big enough! They are like some puffers that need freshwater when young and then saltwater when fully mature. Try chopped clams if it will eat.

 

[simonero]

Good call - I posted in the brackish forum.  I'm hoping to maybe start transitioning once the tank has cycled a little longer and I've done more exhaustive research.  He shouldn't be destined to a short life in the wrong kind of water just because my LFS lied to me!  
 

You also dont know what your water parameters are, tbh its likely that your ph is too low (though id have to double check that) but in brackish tanks it will likely be higher. Its hard to know what results are 'perfect' because ideal paramters are different for each species and seeing as you are keeping a brackish fish in freshwater and its showing signs of not being well, they clearly arent 'perfect'.

 
My pH was 7 last time I checked.  I'm going to re-check asap, just been out of town a couple days (with friends checking on my animals of course!).  So, he IS acting unwell?  What are signs of "unwell" for a flounder?  His behavior is so peculiar in general..  I do notice he's more likely to hang out in clear visibility or off the side of the tank at night than he is during the day.  I don't think that when he is active he isn't any slower than when I got him.  I like to think he's enjoying himself by really exploring his hang-out options in my tank (he sits on the decor now a lot, too) but I also realize I might easily be anthropomorphizing him because I know little about actual fish behavior and WANT to think he's happy...

 

[MBOU]

I think he is the same species as one I had only mine was in a 5ft marine tank and he was a good 5-6" at least!
 
Normal behaviour for him was hidden under the sand with his eyes poking out, he would come out and dart around scooting over the sand and yes, occasionally stick to the glass. He only really ate live feeder shrimp but he would go absolutely mental when they were put in! Wherever the shrimp went, he would follow at speed, knocking other fish and corals and rocks flying in the process lol.

 

[DerpPH]

In the wild they usually eat anything from shrimp to clams and small fish.... I wouldnt go the feeder fish way though.