i have 4 oscars 2 albinos tiger/red black 2 tiger/red and 5 gold fish about 3cm meant to be future food the oscars are about 3cm 1 albino tiger seems to be 4cm growing really fast i did a water change recently my ph levels are at 6.8ph water temp is at 26 degrees . after the water change my black tiger oscar started to hang at the bottom of the tank he has remained at the bottom not eating for about 4 days and the other black oscar has joined him the albinos seem fine swimming around chasing gold fish begging for food i feed my oscars chichild floating pellets the two black oscars hang around the bottom on the tank on the gravel all day looking like they are grasping for air and when they swim they have like this white poo hanging out of them all the time please help btw the tank is 90L i plan to get a bigger tank later on

Hi there and welcome.
As I read your post the first thing that comes to mind is size of your tank.
Not to be rude, but a 90L is gonna be too small for even one Oscar.
Waist will buildt up very fast in such a small tank and oscar's will outgrow the tank in very little time.
You will need to upgrade your tank too keep your fish alive and healthy!

Do you have a testing kit, so you could get us ammonia-nitrite and nitrate levels?
This will help us to pinpoint the problem.
How big is your filter and did you cycle it properly, before introducing the fish?

The white stringy poo may be caused by a (secondary) parasitic infection.
I'm sure some of the others here will help you out in that matter.

i plan to get a bigger tank soon when the money comes up albinos are doing fine just the 2 black ones im worried about

btw wats the ideal filter rate for my 90l tank when i bought my fish tank 2nd hand it came with pump + hang on fitler i have no stats on it im sure i got enough oxygen cuz the air pump is strong the filter seems ok

The only way to make sure if your water is good enough for the fish is to test it.
IMO the water going through your filter 5 times an hour is good.
And regular waterchanges will be nescesary.
I do 50% changes a week with a gravelcleaning.
But a 90l will need more frequent WC.
If you don't have a test set, invest in one.
You're gonna need it!
Were you planning on upgrading to keep all 4 O's?
Cuz it's gonna take a big tank for them!

Noddys giving you some very good advice and asking some very important questions that will help us help you. without test results from your water, god knows whats going on in there. we can only guess. ph and temp are important but ammonia, nitrite, are very important more so than the rest at the mo. I would say take out the gold fish asap.re home 2 oscars, do a 30% water change then 20% daily until you can post those test results. my guess is tank not cycled or filter not coping with fish load. almost certain ammonia, nitrite present. both will damage/kill the fish if left untreated.

welcome to the forum.
Noddy got you covered. i just want o know additional details:
1) how long have you got them?
2) did you cycle your tank first?
while trying to figure out what is wrong, a water change is
a must. whether your tank is cycled or not, you need to do
water change to give the fishes survival chance. the albino
maybe fine for the meantime, but eventually it will suffer
too if you have poor water condition.

i didnt know about cycling the tank first the guy in the aquariam said u need fish in the tank to add the bacteria to eat away at the amonia so i had 6 gold fish put in and started to cycle it for about 1 week or so then i added the 4 oscars 1 gold fish died i did not see it die but the oscars ate it all up i have had fish in the tank for about 3 weeks now.

i have no where to put the gold fish i want to get rid of them but letting them die is to.. inhumane

whats an ideal size tank for 4 oscars in litres

btw oscars are only 3cm still babies

The cycling of a tank will actually take 40 days.
We advice to a 55 Gl at the least per Oscar, so that would mean a 200Gl+ tank.
That's 750+ liters.
Aggression issues not taken in cosideration.
So you either go big soon, or the only sensible thing would be to rehome some of them...
Sorry to be party pooper, but if you keep them like this, they'll probably all die.
Go with Marcus and Paul's advice on WC!

okey then...you are just one among us who make mistake in this
hobby. and i am please to know you have soft heart about inhumane
way of killing other fishes. leave the gold fish and oscar will take
care of them.

cycling the tank normally takes 30 to 45 days before you could
attain ideal water parameters. yes, water prime and/or beneficial
bacteria also help expedite cycling the tank..but adding oscar too
soon put them at risk. you could damage their internal organs and
eventually die.

the ideal size for any fishes is 21 liters of water for every inches
of fish....but fishes, especially oscar, grows fast and a full grown
oscar requires 55 gal of water with good filtration.
(say 10 inches oscar x 21 liter/3.85 lit/gal= 54.54 gal)

you 90L tank is basically 23 something US gal and way too small
for one oscar.... while your o are still small, you can keep them
for a while in that tank but you need to do a daily water change.
and you need to upgrade soon....

lol I mis read and thought 90g not 90l. you need some money FAST. your size tank is ok to keep goldfish but never oscars. they grow far to fast.

Advice given is good. Get a test kit (the bottle type), put some ammolock in. Do daily water changes of 25% until ammonia and nitrite are zero. Take the goldfish and some oscars back to the shop. Get a bigger tank asap, oscars grow real quick. 80-100g will do for 2 oscars, the larger the tank the easier it is to maintain good water. If you cant get a bigger tank then rehome all fish and keep smaller fish

We all make mistakes, i know i did. The thing is to learn from them. Take the advice we have all given to you. Feel free to ask any questions, that is what we are here for. You will get better advice here than from most fish shops. Good luck