FAQs on Oscar
Ich/White Spot Disease,
Dwarf South American Cichlids,
Cichlid Fishes in General,
Oscar Disease 1,
Oscar Disease 2,
Oscar Disease 3,
Oscar Disease 4,
Oscar Disease 5,
Oscar Disease 6,
Oscar Disease 7,
Oscar Disease 8, Oscar Disease 9,
Oscar Disease 10,
Oscar Disease 11,
Oscar Disease 12,
Oscar Disease 13,
Oscar Disease 15,
Oscar Disease 16,
FAQs on Oscar Disease by Category:
Environmental, Nutritional, Social, Infectious, Parasitic, Genetic, Treatments, &
Cichlid Disease 1,
Cichlid Disease 2,
Compatibility, Oscar Behavior,
Neotropical Cichlids 1,
Cichlids of the World,
Thank you for taking the time out of your day to assist me with the
discoloration on my Oscar. I'm so grateful for the work that you do! I'm
very sorry for the length of this email but I want to be as detailed as
possible. My husband and I have researched this thoroughly and are quite
<The length is okay; the 6.5 megs of blurry pix not so much>
I have a 180 gallon tank stocked with two juvenile Firemouth cichlids
(roughly 3" each), two juvenile jack Dempseys (roughly 3" each), an Asian
upside cat fish (5"), a common Pleco (4"), a 10" marbled sleeper goby, a
10" tiger Oscar and a 12" red Oscar.
<A nice mix>
Ammonia reads 0ppm, Nitrite 0ppm, and Nitrate 20ppm. Ph stays consistently
at 8.2. The tank has been running in my home since October and was
previously set up for more than 3 years at my brother in law's house. It has
two CFS 500 canister filters and a custom built 55 gallon sump with
biological media and filter pads that runs
approximately 1800 gph. A 25-30% water change is done each week and if
nitrates go higher than 20ppm (usually after the kids help feed the fish) I
do a 10% water change daily until it is lower.
I use prime as a dechlorinator. We use cistern water in our home, the water
parameters at the tap are 0ppm for nitrate, nitrite, and ammonia. The
temperature is 80°F. The Oscars eat Jumbomin large floating sticks, gut
loaded crickets and mealworms. Occasionally, the red Oscar will steal a
shrimp from the sleeper goby. There was a slight Cyanobacteria outbreak,
however, that was resolved by water changes and switching from t5ho to led
The red Oscar was rescued from a LFS, previously housed with two other red
Oscars (also 12" in size) in a 75 gallon tank before being traded in to the
store. The tiger Oscar was rescued from a Craigslist post. It was living in
a 125 gallon tall cold water tank. It was housed with a Bala shark and a
wild caught Kentucky Bluegill. Both of the Oscars were rescued and added to
this tank at different times in December.
The tiger Oscar started losing patches of color about two months ago. (I
have attached photos of the progression in chronological order.) After water
changes they will either clear up or get worse, it is not predictable. They
are not upraised or "on" the scales and fin. They are also not pitted or
sunken. It is as if some of the scales are losing color and becoming
opaque on the fins. The fins and scales seem to be intact, no
fraying or sloughing. There have been a few instances of a single gill and
fin being clamped temporarily but no other symptoms. Even during the times
with the clamped Gill and fin it had normal behavior. Still eating and
swimming well, no gasping or lethargy. I treated with Prazipro and Maracyn
<Good choices here>
at different times as suggested by a couple of my aquatic enthusiast friends
but have not had any luck in resolving it.
About two weeks ago, the red Oscar started displaying these spots as well.
It has not had gill clamping or fin clamping at this time.
After performing the usual water change this week, the patches have gotten
dramatically worse. (This is the last photo attached)
I am unsure if this is something contagious or if it is environmental
<A wise speculation... I discount the latter; and would REALLY like to
sample these areas, take a look under a microscope...>
but I have had no luck attempting to find the answer on my own.
Thank you so much for looking in to this for me,
<Could be that this issue is protozoan or (still) bacterial... that
Erythromycin/Maracyn didn't "get". I would lace taken foods with
Metronidazole/Flagyl and treat in three doses... as gone over on WWM, the
Net and in reference works like Ed Noga's. Bob Fenner>
Oscars and Hexamita 1/31/17
Hello, i have had so much of a problem with Oscars and i hear they are
supposedly hearty fish.
<Sort of. While they're big, they're also notoriously sensitive to water
quality. This is true for most big cichlids. Virtually all problems with
Oscars come down to poor environment or poor diet. Often a combination
I used to have 2, 3 inch Oscars one was a black and red tiger Oscar and
the other is an albino.
<Used to have...? What happened to them...?>
I have/had them in a large hexagonal tank, when i got the tank i didn't
know how many gallons it was cause it was donated to me. So, i took
measurements of it and found out its a 20 gallon even though it looks
bigger than just 20 gallons.
<Regardless of appearances, 20 gallons is MUCH TOO SMALL even
for three inch long Oscars. Once they get past the "fry" stage,
Oscars are jumbo fish. I'd be looking at 55 gallons, minimum, for
juvenile Oscars; adults
should be provided with at least twice that.>
Last spring i got the Oscars to fill the tank and i love them very much
except a couple weeks after i got the Oscars the tiger Oscar (his name
was Julius Caesar) developed Hexamita on his left gill that just kept
going and going until it ate down his lateral line and completely
through his tail.
<Absolutely typical reaction to poor environment. Now,
the thing here is that while everyone focuses on ammonia and nitrite
(with an "i"), with cichlids, nitrate (with an "a") is the silent
killer. Cichlids are extremely sensitive to nitrate. Because Oscars are
big, greedy feeders the nitrate level in their tanks can go up very
quickly. Anything above 20 mg/l
is stressful, and anything above 40 mg/l will make them sick. A big tank
dilutes nitrate, while substantial weekly water changes removes
It infested his jaw so bad that when he died he didn't have a lower jaw
left, i felt so bad for that fish. When i went to my very informed fish
store owner who has had and sold fish for more than 20 years he
recommended to me that i use Metronidazole, it was MetroPlex by SeaChem.
a little bit in a bottle for 16 crappy dollars that didn't do anything
to help my poor Julius.
<Metronidazole is the correct medication. However, it will not do
anything if the environment is wrong. It's kind of like trying
to treat someone for burns without pulling him out of the fire.>
I treated that fish just about the entire time i had him. Up until about
two weeks before he died (this went on for 6 months) he had a healthy
appetite, had bright colors, wasn't swimming around erratically and
bumping into the tank out side of the regular symptom of Hexamita where
they will swim backwards or lay on their side and he would only use the
one effected gill sometimes.
Some days id wake up and look at him and he wouldn't use it at all and
then the next day he would be using it again. I did regular water
changes and gravel vacs i tried MelaFix and PimaFix both were completely
<In this situation, yes, useless.>
but i ended up using all of it anyway because it seemed to help with
their gill flapping a little bit , the store owner recommended to me
that i separate the fish because they would contaminate each other, and
i used the MetroPlex and Metronidazole treated food except none of it
made the one Oscar better. I didn't have the space to separate them so i
just kept them together instead of getting rid of the other one because
i figured treating them both would help keep the other from getting
infected also (i am too attached to these fish) but the albino Oscar
never showed any symptoms or
had any problems.
<Oscars are inbred now, and there is variation among strains, some being
tougher than others. Luck comes into play too, and being territorial,
non-sociable fish, dominant fish will stress other fish kept with them,
weakening their immune systems. So one fish getting sick while another
stays healthy isn't unusual.>
He wasn't getting the hex his fins were nice he is bright and active all
the time never had any Finrot or PopEye or constipation always has a
good appetite. Except now he has been alone in the hexagon tank since
2016 and its now January. I stopped the treatment of Julius two weeks
before he died because he stopped eating completely the medicine wasn't
helping and i didn't have the stomach to euthanize him myself, i cant
handle killing with my own hand.
The week he died i was sick home from school and i remember watching him
lay on the bottom and his gills just stopped flapping so i took him
outside a buried him with a little gravestone and a small tree.
However now the last day of January 2017 i noticed the albino Oscar has
similar Hexamita pits by his but hole on his side and some very small
holes on his head, they look different like somebody took a pencil and
poked holes clean through my Oscars head, they aren't sores they're
holes. He still has a good appetite. And looks/acts well, i removed the
common Pleco and all the tank decor a week ago because i though they
might be the source of my Oscars wounds, but the wounds haven't gotten
better only bigger.
<You should not be keeping Oscars and Plecs together, certainly not in
such a small tank. Plecs add substantially to water quality problems,
and in some cases they will scrape at the mucous from large cichlids,
causing physical damage and stressing the fish.>
Iv been doing small gravel vacs and water changes every couple of days.
Not a 30% change but just a jug that i had it take about 5% of the water
out and i just fill that with whatever i can get from the gravel every
day or two.i feed my Oscars what ever fish food i have, i don't have a
scheduled and marked calendar diet for them but they get a variety of
food that being frozen brine shrimp, baby brine shrimp, live brine
shrimp, krill, very little bloodworms, Hikari cichlid gold pellets,
metro soaked pellets, wax worms, crickets, and sometimes flake food, and
peas once in a while, I gave them
some cooked tilapia once too but it was a long time ago and im going out
today to get him some live black worms and some ghost shrimp. I use test
strips to test the water, ammonia and nitrites are always at 0 ph is 7,
the water that runs from my tap is hard water but it has no chlorine.
<The fundamentals of the way you're keeping this fish are right, but I
fear tank size is the killer here.>
The water is a little more alkaline than it is acidic, its was at 7.6
that last time i tested except i lost my job and have no more test
strips so i have no idea where its as of this very moment The nitrates
fluctuate a lot sometimes i find they are really high(which i then do a
larger water change) and sometimes i find they'll be really low.
<See above why this matters.>
To put it at an average id say about 25-30 ppm. I have a 40 gal filter
on it that has carbon filter pads in it (i would remove the carbon when
treating my Oscars) and a light, i live in a very warm room and between
the light and my room warmth with the sun by my window anytime i put my
fingers in the tank the water is comfortably warm.
<Oscars are tropical fish, and exposure to low temperatures is quickly
lethal. Anything below 22 C/72 F should be treated as dangerously low.>
I have an air stone that i rotate between my 5 gal my 10 gal my 2, 20
gals and a 75 gal that houses two very large jack Dempseys i have had
fish for 4 years now and all of my tanks are established through the
Please help the fish store owner got stumped and told me i should
euthanize Julius before he died and now my last Oscar is starting to get
sick and i don't know what to do cause iv started using the metro soaked
food and the sores on my albino are only getting bigger with every dose
just like Julius had and i don't want to lose my Oscar. He is the light
of my bedroom i fall asleep every night watching him swim.
<The 75 gallon tank is where the Oscars need to be!>
Could it be something wrong with the tank?
<Yes; it's too small.>
Is it possible Hexamita can be a genetic thing?
<Nope. Nitrate above 20 mg/l is a problem, and unless you're
doing daily water changes, it's unlikely you can keep nitrate that low
with one or two Oscar juveniles in a 20 gallon tank. Cheers,
re: Oscars and Hexamita 2/3/17
Thank you Neale for your advice.
Ill put the Oscar in with the jack Dempseys and see how they get along
<Wouldn't hold out much hope here. Adult JDs can/will pulverise juvenile
Oscars if they feel their territory is being encroached. Oscars are not
really "fighters" outside of breeding, whereas JDs can be extremely
territorial. Not always, but often. I'd be watching these fish very
carefully. I'd remove the JDs first, rearrange the tank so territories
broken up, add the Oscars, turn the lights out, leave it like that for
half an hour at least, then re-introduce the JDs. Standard operating
practise with territorial cichlids, really.>
and if they don't like each other ill get him a bigger tank
<Do suspect this is on the cards; I'd start looking now! Cheers, Neale.>
Sick 9 year old Oscar
We've had our miracle Oscar about 9 years. 10 days ago he
developed a cloudy eye and within 12 hours most of his body was covered
with white cloudy slime. In 24 hours, his other eye was cloudy as well.
<.... a water quality issue almost certainly here. With this fast issues
of these sorts. Water tests, changes stat.!>
We tested his water, which was a bit high in nitrates, but within
<Mmm; how much and indicating what? Ammonia, nitrite?>
We did a 50% water change
in addition to our usual weekly 25%; we found the temperature was too
low, just below 70 degrees, so we heated the tank up. His tank mates
were much happier (i.e. more active). But Oscar now floats on his side
and has done for 10 days.
The white slime became more gunky and has not left him, he barely eats.
He seems to attempt to swim at feeding times and periodically, but with
great effort, like he is having a problem with his swim bladder and
cannot stop floating?
<.... Uhh, how large a system is this? What are the tankmates?
Foods/feeding filtration, aeration spec.s please>
I do not think his belly looks swollen, no protruding anus, I don't
think he's constipated. However, my husband did dose the tank with
aquarium salt 6 days ago (1 teaspoon/5 gallons, dissolved in the new
water during a water change) and started feeding him peas. He is not
interested in the peas, as far as we can tell. Tonight, after re-reading
many posts, we fed him brine shrimp. He flopped about a lot and seemed
to be trying to eat or seemed excited about the shrimp, but really hard
to tell, poor sideways sick guy!
*tank stats: 55 gallon tank, tonight the tank tests pH 7.0, alkalinity
80, chlorine 0, hardness 75, nitrite 0, nitrate 40, sitting at about 77
degrees; we routinely perform weekly water changes of 25-30% and new
filter cartridges as needed, usually every week or two; running two
filters, Tetra Whisper EX30 and Tetra Whisper EX70 plus Whisper30-60 air
<This is all fine...>
We had him in a 29 gallon tank for 7 years,
<MUCH too small... even just for this one fish>
with many African Cichlids, Bala sharks, cat fish, loaches and Plecos,
wherein he occasionally but predictably suffered HITH.
<Environmental stress. This fish has had its life shortened by being
too-confined and poisoned by its own metabolites>
We were thrilled to move him to a.55 gallon tank this last year. Took
the time to cycle it, transfer him safely. He looked strong and healthy
for several months, with the exception of his regular scrapes from
flipping out & swimming violently around the tank. In the *55 gallon
tank currently, we have a 12" Pleco, a 4" lemon yellow African Cichlid,
a 2" Cory cat
(Corydoras) and 2 clown loaches (Chromobotia macracanthus) about 3.5"
and one 3.5" Striped Raphael Catfish. From reading your many entries, I
gather this is an overcrowded situation for Oscar.
<Yes... but mainly due to that Pleco. HUGE waste producers>
I can't believe he's lived so long in a much smaller more crowded tank.
Given the grim state of Oscar and all I've read in your forum, I can
only take consolation in the facts we've never fed him feeder fish or
treated the tank with Melafix, and that he is currently in the largest
tank with the fewest mates in his life. Please advise...Jungle fungal
remedy? Epsom Salt every 3 days??
<I'd just keep the system water quality up and hope. No remedies
will cure this fish>
Oh, we call him miracle Oscar because when he was a wee 3", the African
Cichlids went through a ferocious breeding season and tore his side open
one night. We quickly rescued him, but we could see ribs, he was missing
most of his tail and right fin. In a safe space, he made an amazing
recovery and grew to his impressive stature to become the terror of the
African Cichlids who now hide from him. Hoping for another miracle in
<Thank you for writing completely and thoroughly Amy. Again, if this
were my fish, system, I'd trade in the too-large Pleco (for a smaller
species, specimen) and otherwise, continue your stated maintenance,
offering of favored foods. I am a BIG fan of pellet staples for such
fishes (Hikari, Spectrum are two favored makes).
Wishing your fish health and you and yours happy holidays. Bob Fenner>
Re: Sick 9 year old Oscar 1/13/17
Soooo, the miracle Oscar lives into 2017. He's all cleared up, but
still seems to be having swim bladder issues.
<Likely damaged permanently>
He spends most of his time vertical in the corner. I don't know what his
vent is supposed to look like, but he definitely seems bloated between
his pelvic fin and vent. Poor buddy. He eats about every other day.
A local fish keeper recommended we feed him Koi food, as it is
higher in fiber.
<A good choice>
We have continued weekly 25-30% water changes and biweekly filter
Temp's remained steady at about 77F. Anything we can do to help reset
his swim bladder or relieve his apparent constipation? Amy
<There is a safe, and often effective "lavage" sort of Epsom Salt
treatment that I'd consider. Read here re:
Oscar; algicide poisoned, then "Fix"ed...
I hope you can help me. I have a large Oscar who up until recently has
been very healthy and a good eater. A couple of weeks ago I
treated my tank for an algae problem
<Treated? As in what? Used an algicide? I hope not>
which I think originated from a faulty heater which made the tank too
warm. I have since replaced the heater and keep the tank at 82degrees.
<Too high for an Oscar. I'd set the heater for the mid 70's F.>
I used an algaecide as directed.
<Toxic... Please read here re:
My tank is a 75 gallon and my fish is about 9-10 inches long. One
morning I saw that he had an injury on his head. His only tank mates are
a couple of housekeepers, also large but there has never been fighting
<Oscars are forever "jumping", bumping into things>
When I researched the injury it looked whitish and like bites had been
taken out. I ruled out hole in the head because it just didn't look like
it nor did it seem to bother my fish, Big Red. I treated the tank with a
bacterial medication (Melafix) for a week.
<Of no beneficial use. Search/READ on WWM re this sham>
During this time Big Red stopped eating, or when he did try to eat he
would spit out whatever it was and with it came what looked like little
<Smell the API product.... >
He is still not eating and usually loved frozen peas, romaine lettuce,
meal worms and shrimp also the cichlid pellets. I have offered
everything and he appears to be hungry but the food comes out almost as
soon as it is taken in.
Two days ago I did a 25% water change out which was recommended after
the bacterial medicine regime. No change in his eating habits.
Can you help me?
<Yes... change out about 25% of the water, lower the temperature, add a
pound or so of activated carbon to the filter and try offering food
<Just need to clear out the mal-influences here. Bob Fenner>
Oh thanks. I am so grateful for your help. Just tonight I got
him to eat a little.
Some nibbling at the Romaine a few Cichlid pellets and a couple of giant
meal worms. I am optimistic he is going to survive this.
You were such a wonderful recommendation from the aquarium guy at my
PetSmart. Thank you!
<Cheers Court. BobF>
911 help my Oscar fish please
I recently purchased a 50 gallon tank for my Oscar
and catfish, they were in a 20 gallon tank. I transferred 3 gallons of water
from the 20 gallon to the 50 gallon tank and then filled the 50 gallon up
with fresh water treated. I replaced the 20 gallon with new water
as I always do and treat it. The Oscar usually is upset for the day/night
and then things are normal the next day. I was told not to transfer the fish
into the new tank for a few hours,
<.... how was the system cycled?>
so I instead wanted to wait until the following morning.
When I woke up, the catfish was dead and my Oscar had cloudy eyes and was
very pale in color and had white stuff all over her body.
I transferred her immediately to new tank and rushed to the pet store for
API TC Tetracycline
<Of no use here>
and put the suggested amount in the tank. 5-hours later she was swimming
around and looking lively again. 24-hours from putting the TC in I took out
13-gallons of water as suggested and put new treated water back in along
with the remaining 5 packets of TC. The water turned a dark orange and
developed a layer of gunk on the top of the tank.
<Is the TC HCl>
I had a sample of the tank water tested today and it had high amount
<The root cause here... NOT cycled>
so I drained about 1/2 of the tank and treated it with API Ammo Lock
and the water is registering between "safe .5" and "stress 1.0"
<Won't cycle the system>
Now my Oscar is looking like she's gasping for air. What can I do?
<See above... better, READ here:
and the linked files above... Let's see; you can/could move more of the olde
system to the new, buy/use a cycling product.... Just READ>
video of Oscar gasping for air
photos of the tank
<NO FEEDING, just reading. Bob Fenner>
911 help my Oscar fish please Neale's go 7/31/16
I recently purchased a 50 gallon tank for my Oscar and
catfish, they were in a 20 gallon tank.
<Certainly an improvement, but still far too little for an Oscar above, say, 5
inches/12 cm, and I'm assuming this catfish is some type of Plec, in which case
these need upwards of 55 gallons just for themselves. Both these species are
very heavy polluters, so aquarium volume and filtration are paramount, and water
changes the key to long-term success.>
I transferred 3 gallons of water from the 20 gallon to the 50 gallon tank and
then filled the 50 gallon up with fresh water treated. I replaced the 20 gallon
with new water as I always do and treat it. The Oscar usually is upset for the
day/night and then things are normal the next day. I was told not to transfer
the fish into the new tank for a few hours, so I instead wanted to wait until
the following morning.
<How was the new aquarium going to be filtered? Here's the deal: when upgrading
fish from an old tank to a new tank, all that matters is that the biological
filter is transferred across successfully. Moving gravel across is largely
pointless (unless you're using an undergravel filter, of course) and likewise
moving across "old" water to the new tank achieves very little because the
filter bacteria don't live in the water but on solid surfaces, i.e., filter
media. So, what you should do in a situation like this is take the biological
media from inside the filter belong to the 20 gallon tank, stuff that live media
inside the filter attached to the 50 gallon tank, and then switch the filter on.
Provided the new aquarium water is approximately the same temperature and water
chemistry as the old tank (doesn't have to 100% spot-on) the bacteria will adapt
and your new tank will be instantly mature. You can then move the fish from the
20 gallon to the 50 gallon without problems. If you don't do this, and you
simply add the cichlid and catfish to a brand new 50 gallon tank with brand new
filter media, you'll get a massive ammonia spike, followed within a few days by
a massive nitrite spike, while the filter media goes through it's cycling
process. Adding gravel or water from the old tank will have hardly any affect on
this because, as I mentioned, these don't carry across many bacteria. For sure
there'll be a few bacteria jumping across to the new tank, but only enough to
reduce the cycling process from 6 weeks to a few days less than that. So for all
practical purposes, no benefit worth speaking of.>
When I woke up, the catfish was dead and my Oscar had cloudy eyes and was very
pale in color and had white stuff all over her body. I transferred her
immediately to new tank and rushed to the pet store for API TC Tetracycline and
put the suggested amount in the tank.
<Did you do a water quality test at any point before adding medication? To
summarise: if ammonia or nitrite are not zero, your fish will become sick or die
because of poisoning. While bacteria will take advantage of that, leading to
Finrot, treating the bacteria will not fix the underlying problem, so the fish
will stay sick or keep getting sick.>
5-hours later she was swimming around and looking lively again. 24-hours from
putting the TC in I took out 13-gallons of water as suggested and put new
treated water back in along with the remaining 5 packets of TC. The water turned
a dark orange and developed a layer of gunk on the top of the tank.
I had a sample of the tank water tested today and it had high amount of ammonia
so I drained about 1/2 of the tank and treated it with API Ammo Lock and the
water is registering between "safe .5" and "stress 1.0"
<Anything above zero is NOT safe, no matter what API say! If their test kit
cannot register a zero level, it's not worth owning.>
Now my Oscar is looking like she's gasping for air. What can I do?
<See above. Pretty sure you're dealing with "New Tank Syndrome" going by what
you've said. Substantial (i.e., 50%) water changes daily for the next 2-3 weeks
are surely essential, though do them before adding any medication for that
particular day. While you may be dealing with Finrot as well, it's likely caused
by environmental stress, so fix the environment first. Maturing the filter is
what's needed. Do you have another tank you can donate some live media from?
Established tanks can donate 50% of the biological media without problems.
not eating... Ian? 7/10/16
I have two tanks 75 gal.. set up same way, one power filter and two hang on the
back filters. water parameters are great. no changes to upset. Both raised on
varied diet of crickets worms peas, pellets, river shrimp. Both ten+ inches
raised from birth. One is thriving the other has totally stopped eating. Not ill
or listless yet. What is up? past my knowing. Vet shrugs shoulders and wants to
wait. For it to die??
I’m at XXX.com
<What is the species in question here? Please define "great" for your water
parameters, numbers please. Then I can help you more.> John
Re: not eating 7/10/16
Oscar, textbook. better than the amazon.Have been keeping fish
both salt,reef and south american cichlids over 50 years.First time stumped.
<Assuming water parameters are as you have described, what is your feeding
schedule? I have been keeping monster fish for a long time as well and I often
do not feed for a day or so every week to allow them to clear their systems.
Large fish such as Oscars do not need to be fed every single day. I would advise
moving them to the 300 gallon as it is entirely possible he is stressed out for
being in a smaller sized aquarium. I have never kept an Oscar in under a 100
gallon because they are large fish and can get to lengths of 18"+. My Oscars
right now are around 17" now. I recommend that they be moved when the 300 is
cycled and ready. When is the last time he fed? ~Ian>
Re: not eating 7/10/16
Thanks, I'm waiting for the 300 gal to finish its' cycle, then splash! lol.
I have been feeding all they want every other day since they hit adulthood.
Before this it was 6 feedings a day, till 3 inches. then 3 feedings till 9 to 10
inch size. I considered them adult at 10 inches. I have seen some big Oscars in
the wild. not so much the 17 inch+size, but the thickness. He had one cricket in
the last 4 weeks and this one could eat 5 crickets,10 small river shrimp, then a
couple of grubs or worms. Thanks for the help!!!!!
<Most welcome. Do keep us posted on how the little fella fairs. ~Ian>
Rescued Oscar (any thoughts, Chuck?)
Hello! My husband and I have rescued a tiger Oscar from a young couple
who had him in a tank with NO filter. We put him in an immediate
quarantine tank when we got him home. His story... He is about 10 inches
long and the
couple had him in a 55 gallon that was only filled about 50% (again with
NO FILTER.) The water looked like watered down milk. To top it off, they
had McDonald's happy meal toys as decorations in the tank. While we were
their children were chucking random things into the tank! Food, sippy
cups, toys... Seriously... you name it, it was in there.
<Poor guy; thanks for "doing God's work" as some folks would say,
helping out an unfortunate animal that can't help itself.>
This guy is in bad shape. His gills and mouth are swollen and he can
only open one side of his mouth.. And as you know, these guys are
supposed to be black and orange. He is a very pale grey and his orange
is an off white color. His poop is clear and stringy. We have tried API
salt, slight water changes, and we have just started running an
antibiotic in the tank.
But we still cant get him to eat, he barely swims or moves around. He
has sever indents on his head (no holes) and one side of his face is
distended (the same side that he cant open). The spines on his dorsal
fin are also exposed, and he has some slight tail rot. We have done
everything we can think of to try to bring this guy back to being
Any help or ideas would be grateful Thank you for you time.
<Sounds like this guy has, among other things, Finrot and "Hole in the
Head". Finrot is treated, usually very successfully, with antibiotics.
Hole in the Head is trickier, and requires something specific:
You can use the two medicines together, though the Nitrofuran group of
antibiotics works especially well with Metronidazole, so if you can use
these two together, do so. Don't forget to remove carbon from the
filter, if you use it (carbon removes medicines as well as things that
colour the water). Do remember to provide optimal conditions in the
tank, especially oxygenation. In the short term, food isn't that
important, and if he can't eat, don't worry about it for now. He can go
several weeks on his body fat.
Short term, it's all about stabilisation. Get the fins healing and the
lesions on his flanks healing. I've cc'ed out cichlid expert, Chuck, for
anything else he might add or anything I might have got wrong. Good
Re: Rescued Oscar (any thoughts, Chuck?)
Thank you so much for your swift reply. We will be getting that in the
morning! We will keep you updated as to what happens, if there is any
developments and if we have any further questions! Thank you again.
<Glad to help, and good luck. Neale.>
Re: Rescued Oscar (any thoughts, Chuck?) 4/23/16
I wanted to let you know that I discovered a hole right above his eye,
it looks like someone had thrown a dart at him. It's extremely deep, but
small in diameter. I went to the store and bought some Metronidazole.
<That's the ticket!>
We have started that process, hopefully he pulls through! Thank you
again for the advice! I'll keep you updated.
<Does sound like typical damage to the sensory pores caused by Hexamita
infections and/or Hole-in-the-Head more generally. Do read up on these.
While Hexamita is treated with Metronidazole, it's a pathogen that seems
to work alongside other problems, specifically poor diet (i.e., lack of
green foods/vitamins) and high nitrates (i.e., lack of water changes).
Obviously your fish is a rescued fish, so the causes aren't your fault,
but going forwards, you will need to keep these two in mind in the long
term. Good luck, Neale.>
Sick 7 yr. Tiger Oscar, HITH
My 12 in. 7 yr. Old Tiger Oscar lives in 75 gal tank with 2 306 Fluval
canister filter a 400 mainland hob. He developed hth. from over feeding
<Hole-in-the-Head? Rest assured that this is treatable, though you do
need very specific medications, and need to medicate promptly.>
I treated with MelaFix and then Ali general cure as directed.
<Both useless for this. Hole-in-the-Head is partly related to diet,
partly to water quality, and partly to a parasitic protozoan called
Which is the most important of these remains a matter of debate! But you
need to consider, and tackle, all three. First, diet. Stop
feeding if water quality isn't good. When you do start feeding again,
you need to ensure plenty of fresh greens. Oscars are often overfed junk
food, most dangerously of all, goldfish and other live foods. When
hungry, they will eat plant foods, and these provide essential vitamins.
Grapes, melon and other soft fruit are all worth a shot. Cooked peas are
generally taken without fuss. Feel free to starve an adult for a week or
more to get them
interested! Secondly, check water quality. Ammonia and nitrite MUST be
zero, and don't feed if they're not. But crucially, nitrate must be low
as well, 20 mg/l is the upper limit for good health; even 40 mg/l is
stressful in the long term. So, a spacious tank, minimal food given to
the fish, and lots of water changes are usually the key to success when
it comes to nitrate. Finally, medication. For Hexamita, you need
Metronidazole. Often used alongside an antibiotic, but Metronidazole is
the silver bullet here.
Nothing else works. Be sure to remove carbon, if used, from the filter
Every spot cleared except 2 holes near his eye that still look pink. He
won't eat his works or any thing ! Does he need antibiotics ? Please
I'm disabled he's my therapy pet and friend .
<Well, I hope all of the above helps get him back into shape! Good luck,
Oscar fish; growth 4/6/16
Hi ☺️ I was given your email address in the hopes you might be able to
give me an idea of what I should do with this guy. He developed this
lump before he was given to us but just in the last week or so it has
gotten a lot bigger and looks sore. Thanks,
<This growth looks to be tumorous; no treatment available directly.
Doing your best to provide good care (hard, alkaline water of low
nitrate/metabolite content; good nutrition...) is about all one can do.
As far as I'm aware no medicines will reverse this growth. IF you decide
on euthanizing this fish, I'd have you read here:
Strange Oscar Problem. 3/4/16
Hello, I have a Red Oscar in a 70 gallon aquarium, he recently developed
a weird skin condition that looks almost like he was rolled around in
salt. It doesn't look like any aquarium disease that I have ever
before. The strangest part is that his behaviors haven't changed much if
at all. He will still eat just as much and he is not lethargic at all,
especially when he is running away from his tank mate. Any help would be
<Whitespot/Ick or Velvet. Find a medication for these and treat
accordingly. Remember to remove carbon before using any medication.
FWIW, Whitespot/Ick tends to look like salt grains, Velvet more like
sugar, often with a golden sheen. Both usually follow on after adding a
new tankmate, which includes feeders (which you shouldn't be using, and
hope aren't, but it's worth mentioning just in case). Cheers, Neale.>
5yr old Oscar; Dis.; env. 1/27/16
My Oscar has been struggling for q month.
I have tried to get the water balanced but one nitrate is 80mmg and the
ph is low still...
<You must keep nitrate below 40 mg/l with Oscars. Above this and they are VERY
prone to health issues... Hole-in-the-head for example. If you have zero ammonia
and nitrite, that's good. It means your filtration is adequate. But nitrate at
80 mg/l is very worrying. High nitrate means a combination of overstocking,
overfeeding, and insufficient water changes.
To recap: Oscars need big tanks (75 US gallons minimum) and should substantial
(25-50%) receive water changes weekly. Feeding should be extremely moderate.
Oscars will easily eat far too much. Portions about the size of the eyeball are
a good start, no more than one meal per day.
Skipping meals once or twice a week is a good idea, too.>
He now has a fuzzy white growth on his eye and white stuff on his fins and body.
<Finrot and/or fungus; fix water quality problems, and treat accordingly with a
reliable medication. Not Melafix and other tea-tree oil products; something like
Kanaplex for example.>
He looks almost like he blowing water out his mouth with white stuff in it.
I can see the ragged looking skin in his mouth. I did notice the heater isn't
working properly also.
<Anything below 18 C/64 F is lethal to Oscars; between that and, say, 24 C/75 F
will be stressful. These are tropical fish, and hothouse flowers at that! You
need a reliable heater, probably outside the aquarium because Oscars can/will
destroy glass heaters in the tank. Eheim make an excellent range of combination
heater/filters that work great with Oscars, but there
are nice "inline" heaters from Hydor, among others, that you can connect to the
outflow from the external canister filter. External canisters are pretty much
the only option for keeping Oscars on a budget because you need a BUCKET of
biological media, so using inline filters isn't a major ask.
Even better are sump-type systems (as used for marine tanks) where a glass
heater can be put in the sump instead of in the main tank.>
The temp is fluctuating a lot.
<Killing your fish, alongside the high nitrate.>
Please help he has eaten in at least 5 days
<Least of your problems. Oscars will literally beg for food when healthy.
Any Oscar that doesn't is, at best, stressed; at worst, sick/dying. Review,
quickly, and act accordingly. Hmm... let me direct you to some reading...
Oscars are easy fish to keep if you have "all your ducks in a row", but if you
try to cut corners, they'll quickly get sick. So: giant aquarium, massive
filtration, external heater of some sort, cautious feeding. Sound good? Cheers,
RE: 5yr old Oscar 1/27/16
I am going to have my water checked and get a new heater and
meds....with the water change do you recommend. He's obviously stressed.
<Indeed. You're aiming for:
average 0-20 mg/l nitrate; certainly no more than 40 mg/l before you do a water
stable pH around 7, but anywhere between 6 and 8 is fine so long as it doesn't
vary much, though bear in mind below pH 7 biological filtration works less well;
water chemistry soft to medium hard;
temperature 25-28 C/77-82 F.
RE: 5yr old Oscar 1/27/16
And also how do you remove the high nitrates?
<Three steps. First, understock the tank so nitrate builds up slowly. Don't try
and keep an Oscar in 55 gallons, and don't keep them with other fish unless the
tank is huge (I'd reckon at least 100 gallons before I thought about adding a
catfish for example). Secondly, don't overfeed; again, so nitrate builds up
slowly. Finally, do frequent, substantial water changes.
Up to 50% every week would be about right, but even better is frequent smaller
water changes, say, 20-25% every couple of days. Of course this assumes your tap
water has low nitrate. The higher the nitrate in your tap water, the more often
you need to do water changes. If you have high nitrate tap water, you may prefer
to use RO water buffered using commercial
Discus Buffer; do read up on this approach carefully though because very soft
water can cause problems if incorrectly buffered and prepared for use.
RE: 5yr old Oscar 1/27/16
I just don't get how he's been fine 5 yrs then all of a sudden he's sick and
<Sometimes the question is not "why's he sick now" but "how come he was healthy
for so long"? The answer can be simple luck. But do understand fish get bigger
as they age, filters clog up over time, jaded fishkeepers do fewer water
changes... eventually a tipping point can be reached, after years of success,
and a big, old fish can get sick.>
i lost a algae eater a few months ago and he must've kept it pretty clean...
<Algae eaters remove algae, a bit, but don't keep the tank clean. By definition,
every extra fish makes water quality WORSE. More ammonia excreted, more nitrate
building up between water changes. How big's this aquarium? What sort of filter?
genie Bohlke & Robins 1968,
Cleaner Goby. Western Central Atlantic: Bahamas and Grand Cayman Island. To 4.5
cm. Bahamas and Grand Turks images. Bold yellow V marking on head trails into
pale band along sides. St
RE: 5yr old Oscar 1/28/16
Its a 30 gallon and the filter that came with the tank.
<Well, and Oscar in 30 gallons is rather like keeping a horse in a shed.
The filter is probably coping if it's a decent size and been there for years,
but the tank really is too small, and upgrading the tank to at least 55 gallons
is the priority. Upgrading the filter is worth doing, but the tank is the first
issue to deal with.>
I never expected to have such a large fish he was only about 3 inches when we
<Oscars grow very fast!>
Im going to get a new filter\pump today. I got the fungus medicine. And treated
<Anti-fungus won't treat bacterial infections. So can be a waste of money.
Fungus is distinctive: looks like cotton wool growing from the fish. Long,
off-white threads. Bacterial infections look different, usually.>
But it says treat again in 48 hrs then do a water change after 48 more. I think
he'll die before then if i don't change the water first and then do the
medicine. They didn't have the kind you recommended KanaPlex. But had API brand.
I hope that's ok.
<Can't tell if you don't tell me API "what" medication. You need something that
treats fungus and bacteria if you can't tell them apart. In the UK, I
use/recommend eSHa 2000.>
It turned my water green.
<Sounds like it contains Malachite Green, but tell me what the medication is
called and we can help further.>
I went to pet supermarket and they were absolutely no help. So I'm on my own. I
had my water tested there thinking it was a different test but it was the same
strips! That was a waste of time. He told me what I already knew and no one
there knew anything on how to help. The only help I've gotten figuring this out
is you. Ph is low alkalinity is low, water is hard, nitrite is 0 and the
nitrates if off the charts.
<Low nitrite suggests the filter is basically okay, or you'd detect nitrite (and
ammonia). But nitrate is produced by a filter, and removed by water changes, and
accumulates faster the bigger the fish and the smaller the tank. Make sense? So
"off the charts" nitrate suggests a big fish, a small tank, too much food, not
enough water changes... some combination of those
anyway. Nitrate is a slow killer. It stresses fish, but short term spikes aren't
a problem. Long term exposure makes them sensitive to other problems and
I've done 2 water changes in 2 weeks. Im scared of putting to many chemicals at
once that one will mess with the other. Im so lost.....i feel as if he's going
to die because of my ignorance....
<Here's what I'd do. Most medications work for a few hours after use, then fade
away in the tank. So I'd add the medicine first thing in the morning. I'd go to
work, come home, have my dinner, and then, say, 8 or 10 hours after the medicine
was put in, I'd do a 25% water change. I'd repeat this process for as long as it
takes. When the medicine is done, I'd still keep
up with the water changes, if not daily, then every 2-3 days. I'd feed
minimally. On top of this, I'd be looking at a bigger tank. Finally, do remember
to remove carbon from the filter if you add medicine. Carbon removes medicine
from the water. In fact I'd not buy carbon or use carbon at all! Cheers, Neale.>
RE: 5yr old Oscar 1/28/16
He does have the white furry fungus on his eye and the white stringy stuff on
his body a little bit not much.
<Good. There's hope then!>
As far as the tank foes my other half (husband) was suppose to be taking care if
the tank....im supper ticked at him!
<I bet. Oscars are easily overfed. They actively beg for food, and worse still,
some people feed them live goldfish and other very unhealthy foods.
So it's super-easy for them to become sick if you aren't careful. Feed small
meals, skipping the odd day.>
When I realized he was feeding him too much and not properly doing water changes
I have taken over!! Now he's my fish! I will do what I can to save him! Thanks
for all your help! I put in the meds last night. I attached a pic of the front
and back of the medication box.
<Looks promising. "Secondary bacterial infection" is very likely what you have
here along with the fungus, so with luck, you'll be fine with this.>
His tank is proper heated now. I am doing a water change today! What type of
filter do you recommend if not carbon?
<Just remove the carbon. If you can, replace that segment of the filter with
biological media, even filter floss, which can buy loose in bags. If you can't,
just leave that compartment empty for now. Carbon is a menace if you're trying
to heal a sick fish! Cheers, Neale.>
RE: 5yr old Oscar 1/28/16
How do I get water that is ok to put in there every couple of days?
<Assuming your water chemistry is reasonably stable, you can buy the quite handy
"automatic" water changers -- the "25ft Python No Spill Clean And Fill", for
example. Drain out 25% of the water from the tank, add dechlorinator, then use
the Python to take water straight from the tap to the aquarium. Alternatively, 3
to 5 gallon buckets are cheap and obviously
work great, they're just harder work. Don't change more than 25% of the tank at
any one time unless it's an emergency because it's hard to keep water chemistry
and temperature constant. Now, if your water chemistry varies (often the case
with well water for example) you might want to draw the water into a bucket, and
let it stand overnight before use.>
I have 5-1 gallon jugs I use. But that is clearly not enough! Any suggestions??
5yr old Oscar 1/28/16
Figured I send a pic so you can be introduced...this is Sushi.... And his sick
<Doesn't look too far gone, but yes, a bit rough, that's for sure. The eye looks
swollen... would use Epsom salt alongside other medications... do read:
Hope this helps, Neale.>
RE: 5yr old Oscar.... 1/29/16
Lol im sorry but I could not understand ALL the info on the salt. I don't have a
problem doing it. I would think it would hurt him a lot to have the salt burning
<Tears are salty, are they not? Eyes are meant to have salty water around them.
So don't fret.>
Just a question. How much can I use? And how often?
<Dosages all in the article...
2 gram/litre for the aquarium salt; for Epsom salt, 1-3 teaspoons per 5
gallons/20 litres. As always, dissolve thoroughly in a jug of water before
adding to the tank. Also, remember that if you do a water change, add the
appropriate dose to any new water on a per-bucket basis. So if you replace 5
gallons of water, the new 5 gallons of water has to have 1-3 teaspoons of
Epsom salt added. Don't make the mistake of adding the amount needed for the
WHOLE tank per water change otherwise you'll make a right mess and probably kill
your fish. Do read, digest, reflect. One of those times basic
maths is important! Cheers, Neale.>
RE: 5yr old Oscar 1/29/16
1-3? So do I start with like 1.5 teaspoon s per 5 gallons to be safe or 1?
<Choose something between 1 and 3, less for safety, more for serious situations.
But even 3 teaspoons of Epsom salt per 5 gallons/20 litres of water is safe with
cichlids. DO UNDERSTAND this is for Epsom salt (magnesium sulphate), not
aquarium/table salt. For aquarium/table salt (sodium chloride) I'd weigh out the
salt using kitchen scales if at all
possible, so you can keep to the 2 gram per litre of water amount. Google will
tell you how many litres your aquarium has if you're used to gallons... for
example 30 US gallons is 113 litres. Multiple the 2 gram by 113 to get a total
of 226 gram per 113 litres (or 30 US gallons) and weigh that amount out
carefully. Or don't use salt at all if this is all too terrifying.>
I. Sorry I've just don't been trying to save his life and im scared of
overloading him...thank you so much....hr ate a little this morning...
<A good sign. Neale.>
RE: 5yr old Oscar 1/30/16
I fear he will loose his eye though...
<Definite possibility. FWIW, fish can manage just fine with one eye. But fingers
5 yr old Oscar 1/30/16
I am so discouraged. I have bought
a $ 100 worth of stuff and CANNOT get the nitrates down. And he isn't getting
better... I have changed 25% of the water 3 times in 5 days..... I don't know
what else to do but drain the whole tank and start over....i could choke my
husband! Sushi's eye looks horrible also......
<Nitrate won't go down immediately. It'll be diluted by each water change
though. So if you have 100 mg/l, do a 25% using water with zero nitrate, it'll
go down to 75 mg/l. Your test kit may not even register the change.
Furthermore, your water probably has some nitrate, so the reduction will be even
less, and on top of that, the fish is excreting ammonia and that means the
filter will be producing nitrate! Bottom line: stop feeding, do 25% water
changes each day, perhaps twice a day if you can with a few hours between them,
and after a week or so you should find nitrate lower. Make
sense? You're learning now while nitrate is harder to "cure" than "prevent" via
water changes, under-stocking, and not feeding too much. Neale.>
5yr old Oscar 1/30/16
So last night I did a water change and medicated him this morning. He did eat
this morning. I assume that's a good sign.
<Yes, but I wouldn't go crazy. A little treat of a snack, that's all!>
However the nitrates are still high. Another water change tonight. But his eyes
still looks bad. I know you said something about aquarium salt but im kinda
scared of that
with everything else im doing to his poor soul! I tested the water I had sitting
in jugs and it was perfect. But this morning the ph is below 6.2 so is the
alkalinity. The water is still hard and the nitrates are still high....not
giving up yet.....just curious about adding salt. I don't want to overload him
and stress him put more. Another thing...he keeps like coughing out white stuff
since I started the meds is that normal?
<Not abnormal, anyway.>
5 yr old Oscar. Reading... PLEASE!
Thank you so much for corresponding. My water that im putting in doesn't have
nitrates I checked. However today the nitrites is a lil high along with the
<Please read here:
and the linked files above>
So far there were 0 nitrites. It was a little last night but a little higher
this morning.....poor fellow I am slowly killing him I
believe.....he still has a little bit of the stringy stuff (not alot)
<No such word. It's a lot>
but some. His eyes is still in rough shape. I guess I will change it this
morning but do I put salt in the new water every time?
<Just the amount, percentage removed>
And also what about the temp fluctuating so much with all the changing of the
water will that make him worse? One more...sorry do I keep putting fungus meds
<The same as the salt; per the API instructions. Bob Fenner>
5yr old Oscar 1/31/16
Im sorry to say but Sushi is not doing well... I changed his water again today
25% and added salt to the new water which was 2.5 tsp to 5 gallons and water
conditioner, and fungus meds. I gave No food today. He acts like he has no
balance.....staying in one place most of the day and going nuts when im doing
anything to the tank..... I don't know what else to do.....now the nitrites are
<What are your water quality readings? Ammonia, nitrite, nitrate? Hardness, pH?
RE: 5yr old Oscar 1/31/16
Well I have the dip sticks.
<Neither accurate nor precise. See WWM re>
The nitrates haven't changed In over 2 weeks they are still 100+
<ppm? Waaaay too high. DID you read where Neale referred you? High [NO3] is a
1) Too small a volume, tank size relative to:
2) Biomass (stocking), and
3) Foods, feeding, along with:
4) Capacity of ones filtration (mainly bio. and chem.) AND
5) Maintenance practices...
Your Oscar IS (?) in at least a 55 gallon?
No other animal livestock present?
You're scarcely feeding proteinaceous foods?
You've added to filtration PER YOUR READING to enhance bio. (and poss. chem.)
the nitrites are .5- 1
<Deadly toxic at high pHs... again, ARE YOU READING?>
where they were 0..... my sticks do not have the ammonia readings......I don't
know what else to do for him
<Less feeling and more understanding what is going on here. READ the items above
and respond honestly>
.....and his eye still looks band.....no better at all....i just checked on him
and he is still alive but just hanging in there.....�� I feel horrible for him!
<... What are you going to do? B>
RE: 5yr old Oscar..... reading for comprehension, or at all. Env. dis.
Im sorry but I have read ALL the info that Neale referred me too.
<Ah good. We have some 30k users per day... WWM is a reference site, not a
I don't quite understand all of it but I do some of it. Im writing you back with
the info to what I've done so far that Neale has educated me on what to do.
However I am not a expert by any means and I don't really appreciate all the
unnecessary comments like did I read anything!
<Sorry to state; but this is how it appears... w/ your writing back that you
don't know what to do. Had you read clearly you'd understand>
Yes I have and I know these things are toxic but I have done everything Neale
told me to do on top of spending alot
<.... again; no such word>
of money. I have really been trying but everything I have done and its only
worse. The water doesn't even look healthy. Its orange looking brown on the
bottom half of the tank and green from the meds on the top half. He is so
stressed from all the water changing and cleaning his tank everyday. He cant see
out of one eye so he's even more stressed.......so frustrated....
<Go back and re-read where you're been referred to. You fail yet again
to answer my direct questions. Your statements tell me/us little of substance;
comments re your feelings are of no use. B>
RE: 5yr old Oscar 2/1/16
<Don't write: READ>
Don't get me wrong please I am very thankful for all the advice......I just
don't know what else to do but drain like 50% of the water.....if I don't do
something drastic he is going to perish from not being educated. I really want
to choke my husband because he was not doing it correct this while time or even
at all. yher is no other fish in a 39 gallon tank....hes been the dame size for
2 yrs but my heater had stopped working properly and u didn't realize till it
got very cold last week is when he started showing signs..his eye which is lost
im sure by now and the clear stringy stuff on his body which he doesn't have
anymore as far as can see... His eye and the water so toxic is what im concerned
for. I cannot by a new tank at this moment. I just spent $100 this past week on chemicals,medicine, new water conditioner that reduces nitrates and nitrites and
new filter with no carbon, new air pun for more ariation and Epsom salt. I've
changed the water 3 times in 6 days actually 4 because im about to do it again.
My tap water does not have either nitrates it nitrites in it...so im stumped aa
to why it doesn't lower and now the other nitrites are showing. I just feel he
needs new water maybe.....im no expert for sure but the water looks old and
stinks of old water...
RE: 5yr old Oscar 2/1/16
Thanks for all your help but I do have to say I really appreciated
Neale's help ALOT <sigh> more than yours. I am truly sorry for
expressing any "feelings" about my pet that you have no use for or agree with.
Apparently I cant read nor do I know what a real words! Havea good evening Bob.