Why does my Oscar fish lay on the bottom?

Do you have an Oscar fish that lays on the bottom of the tank sometimes? Does your Oscar fish seem to sleep on the bottom? Does your Oscar pout in the corner if you have to mess with stuff inside the tank? Why does my Oscar fish lay on the bottom? If you’ve ever asked any of those questions, we’ve got some answers for you.


For starters it is not a cause for concern and in most cases this is perfectly normal. The Oscar fish is quite temperamental and sometimes they just pout. Mine will lay in the corner if I have to move stuff inside the tank, almost every time. If you leave for a few minutes and come back, he is usually back up and swimming around. If your Oscar lays on the bottom for days on end this could be the sign of a problem though, so check your water parameters if that is the case.

It is not uncommon for them to rest on the bottom from time to time. They may do it because of stress, it is really hard to say. Mine will sometimes take a bit of a rest on the bottom after a big feeding session as well. So, many factors can contribute to an Oscar resting on the bottom but in most cases it is nothing to worry about. As long as it isn’t for days on end and the fish is still active and eating an occasional rest on the bottom is not cause for concern. If you are concerned it doesn’t hurt to run a water test to make sure all the parameters are good, as long as they are your Oscar should live a long and healthy life.


  • Kaye says:

    I have a 14inch tiger Oscar who is about 4 years old. He has a 15 pleco as a tank make. They have been together since they were fry. I have a 55 gal and I recentley added a 6 inch jack dempsey. My Oscar is laying around like he is lathargic. What do I do?

    • TankTerrors says:

      I would suggest removing the Jack Dempsey and getting it a separate tank if possible. That tank was already well over the limit with a full sized Oscar and large Pleco. If you want to keep the JD with them then I suggest no smaller than a 125 gallon for that trio due to the large waste load all 3 fish produce. You must keep up on water changes and such pretty well if you’ve managed to grow an Oscar that big in a 55 gallon, so just keep doing water changes for the time being because it will foul up fast with those Monsters.

      The JD can be aggressive (and have teeth) and Oscars can be passive, so he is probably sulking and pouting because of the new tank-mate in the already cramped space who may or may not be picking on him. If you can get the JD his own tank, a 6″ guy would be alright in even a 20 gallon as long as it wasn’t permanent. Then you could give him the 55 gallon and upgrade the Oscar tank. Anytime I moved my Oscar or changed something he would pout but as soon as he got put back in my old 200 gallon he’d perk right back up. They don’t like change as odd as it seems, good luck. Hope this helps.

      Oh and you can find cheap tanks on Craigslist by the way, usually some careful looking can net you a tank for around $1-2 per gallon – so you can get a 100+ gallon for under $200 and many times they’ll include filters and stuff.

  • my oscar fish is laying on the bottom he has been doing it for two days now and i took a look at the water what do i do

    • TankTerrors says:

      I would do a 50% water change even if it tests out fine. If you’ve added any other fish or anything else, that could also be the cause. They get stressed out easily as tough as they seem.

  • i have a nother oscar fish in the with my other oscar fish could that be the reason why he is laying at the bottom of the tank

  • he is getting bullied by the other oscar

    • TankTerrors says:

      Then that is why he is laying on the bottom. You either need to put them in separate tanks or at the very least put a divider in there to keep them apart. Those are really the only solutions aside from getting rid of one of them to a friend or fish store.

  • i have dividers but there all to small

  • i have other tanks but all my filters are all broken and my friends don’t want the other one and the pet store won’t take the other oscar and i don’t have a enough money to buy a new filter what do i do

    • TankTerrors says:

      Buy some cheap acrylic at a home improvement store and make a divider out of it. Smaller thin sheets can be bought very cheap. You can also use white plastic egg crate at home improvement stores, it is also known as light diffusing panel for even cheaper.

  • Zak Lucous says:

    How can I get my Oscar fish to move? He is no longer than 3 inches and I have him in a 45 gal fish tank that has been filtering for 6 weeks

    • TankTerrors says:

      If he is laying on the bottom he is either stressed or the water quality isn’t up to par. Do a water test and change if needed. If that doesn’t help then perhaps another fish is bullying it. It could also be stress from a recent move.

  • Gagan says:

    I ve a white oscar one year old wid 3black sharks also 1 year old.. From past 3 months its layin on the bottom 24 hours.. Only comes up whn i feed.. Its a v beautiful fish i dont want to let it die.. I dont find any sign of fungus infection on it.. My aquarium is 3 feets by 2 n half feets a standard size.. Pls suggest me somethng

    • TankTerrors says:

      What gallon size is your tank? What is the depth from the front to back? It sounds on the small side for an Oscar. I would suggest a large water change followed by a water test. Make sure there is no Ammonia, Nitrite, and less than 10ppm Nitrate. If there is do daily water changes until those readings are achieved. They can be moody fish but often times are stressed by poor water quality. It is a good sign he is eating but he shouldn’t lie on the bottom all the time so something is likely wrong or it is stressed from something. Sometimes they can be sick with no external signs though. Also make sure the light cycle is consistent with a timer, do not leave them on all the time. Best of luck with your Oscar.

  • Thiare says:

    Im concerned my is belly up but still breathing and swims but belly up! What should i do? He looks dead as soon as i move him to place him right side up he goes back down :(

    • TankTerrors says:

      You could try doing water changes to make sure the water is perfectly clean. Aside from that the symptoms you have mentioned are usually a very bad sign. Sometimes a fish can make it through but often times going belly up is a sign that they have a serious problem. Best of luck with your Oscar.

  • Pebbles says:

    Please help I have a 5in oscar had him since april 1 2014 started out great shy for a about 3 days he was about 1 1/2in when I got him so he’s been growing nicely would come to front of the tank when approached an then about a month ago he started hiding all the time he acts very scared now I have to shake the food now to get him to come out an he doesn’t eat nearly as much as he was I feed him twice a day he’s in a 75 gal with a Raphael catfish that only comes out when it’s pitch black in the room my levels are good ph 7, amo 0, nitrites 0. Nitrates 15 the only thing that I can think of is i got some pond snails from the lfs here an put them in the tank for the assassin snail that was in the tank he ate most of them before they hit the bottom an a few days later I notice little white things on the glass which I have since found out are limpet snails an I don’t know how to get rid of them an they are breeding badly. Oh an my temp is 80 an I do wkly 50% wc. Please any help would be great.

    • TankTerrors says:

      It could be the snails doing something to the water, but it’s hard to say for sure. If the water reading is still good, then he may just be moody. I don’t know much about snails but you may want to check out some fish forums or snail forums to see if they release anything into the water. The tank size should be good. Is the lighting on a schedule? If not try to keep it on a timer so it is consistent. Good luck. A water change never hurts though, so if all else fails try that.

  • Pebbles says:

    I turn his light on at 10 and off at 830 pm. Is that to long?? I have searched an everyone says those snails are beneficial to the tank I hate them personally they make my glass look dirty but I don’t want to use chemicals to get rid of them. Thanks so much for the help hopefully he will come around.

  • Pebbles says:

    Ok I did some more test today an my ammonia is now 0.25 ph ,nitrite , nitrate had no change what can I do?? Thanks for your help

    • TankTerrors says:

      In that case you will need to get a water change done to bring the ammonia down. Adding some Prime water conditioner will help make the ammonia less toxic in the meantime. It appears you tank is either still cycling or going thru a mini cycle. If you washed your filters recently and used tap water instead of tank water you possibly killed most of the beneficial bacteria that convert ammonia into less harmful nitrates. It will catch back up eventually but just watch ammonia levels in the meantime.

  • Pebbles says:

    Ok I’ll do a 50% wc now I use prime all the time I do rinse the bio balls an ceramics in the tap water never really thought about that being bad would it be ok to use distilled water. I use the syphon that attaches to the faucet so my tank water goes down the drain. Thanks again

    • TankTerrors says:

      You could use distilled (you can use anything really as long as it doesn’t have chlorine like tap water does) – or another option is to just scoop out a few large cupfuls from the tank and use that water to rinse the bio balls in a bucket.

  • Pebbles says:

    Ok thanks for the help

  • Avnit says:

    I have two a black oscar.One Just come up while i am serving food to fishes.Rest time she comes up or swims very rarely.The second oscar swims rarely well.Is there is any problem with the one that dosent swim.

  • Avnit says:

    This black oscar is in good condition doest not have any white spot and is alive from small age but dosent swim to much.

  • lloyd says:

    Sir, I have two 2year old Oscars. A male and a female. Both are so attached… They swims together.. Eat together… How can I mate them…? What are environmental situations for the to ate. I have a heater un my aquarium which is set to an 30 degree Celsius. The tank is 30 inch long,15 inch width and height. Plz help me.

  • lloyd says:

    What are the environmental Conditions for them to mate.
    I have a heater in my tank at 30 degree Celsius. The is what I meant .
    Sorry for the inconvenience. Please reply.

  • rhys says:

    I have three oscars all juveniles. One red one tiger and one wild type in with a few fancy plecs gold nugget, sunshine, green phantom, tank is 800 UK litres.. as they grow will the wild type be too aggressive for the other two? Thanks

    • TankTerrors says:

      It is really hard to say, it can help if they grow up together though. However a fish can decide to be a bully any time.

  • skilla says:

    i have two baby oscars i purchased at the same time 1 is amaziningly active the other has been laying at the bottom of an on for a few days

  • Dan says:

    Hello. I have 3 oscars which are really energetic for weeks after i got them .i went out of town for 3 days and i told my cousin to feed them. After i returned they were lying down on the bottom of the tank. Its been 2 weekw now. But every feeding time they always come back up and they are energetic. My concern is they are spending MOST of the time on the bottom of the tank doing nothing. Thanks a lot for the help.

  • Lester says:

    Hello i have 6 oscars for 4days now….this time i feed them with shrimp…and after i feed them they all stay at bottom of the tank…i dunno if i feed them too much…:(

    • TankTerrors says:

      If they are feeding that is a good sign, they may have just eaten too much that day. Just make sure the water is clean and they have space.

  • zachery says:

    Hello, I’m not sure if this is the correct forum to ask this question but yesterday my 5in tiger Oscar had decided to eat my one inch pleco sucker fish, he ate it head first but could not swallow the rest, my brother and I stupidly decided to rip out the rest of the pleco from his mouth and now his lip looks dislocated or something, is there anything I can do about it or will it go back over time, please help.Thanks

    • TankTerrors says:

      You may have broken some of the structure of the mouth. I would not mess with it anymore and hope it can heal up on its own.

  • Dylan says:

    I have a new Oscar bout 1.5 years old and he is with a butterfly catfish. He lays on the ground on his side a lot and the catfish is always under him trying to get his to swim. Well that’s what it looks like. The temp is a good but he is always doing it. What do I do

    • TankTerrors says:

      As long as the tank is large enough and the water parameters are good there isn’t much more. He may still be adjusting to the new home.

  • Chris says:

    My Oscar has been laying on his side In tank now for three days an loosing his slime coat. Did a water change an treated. All I can think of is maybe he caught something from the fish I feed him was doing fine till I added new fish to feed. I don’t do it often but this time messed him up.

    • TankTerrors says:

      I have been away for a while, hopefully you were able to get it taken care of.

    • TankTerrors says:

      If he is losing his slime coat that is a bad sign. You can try to treat the water when that happens but something is out of range for sure if he is losing the slime coat.

  • bree says:

    SOS to all my fish owning friends. I need help, I have now adopted an Oscar & a pleco. both babies, I know they will need a bigger tank as they grow. BUT in the meantime- they are stressed from the move & new environment. I’m new to the hobby, & I need advice on how to save my new fish. both of them are being very lethargic. the pleco is not sucking on anything anymore, & the Oscar is not eating much, and a also laying on the bottom of the tank. he looks like he is seriously dying. I’m getting a test kit tomorrow to get the ph ammonia nitrite and nitrate levels. I conditioned the water before putting them in, cleaned everything. I feel as if I ruined the beneficial bacteria by using tap water… I’m new at this and definitely did something wrong. please help me save my fish.

    • TankTerrors says:

      I have been away, hopefully with the testing kit you were able to figure it out. Tap water is ok to use but if the tank wasn’t cycled it likely had an ammonia spike once the conditioner wore off.

  • Cheeto says:

    Okay I got 125gL tank
    3 tiger oscars (2 black/orange/brown and 1 albino) all about 7inches size of hand
    1 Jack Dempsey 6inches
    1 pleco about 4inches
    1 parot 3inches
    1 spiney eel of some sort
    2 assorted cichlids (light blue yellow dot on tail and a small orange)
    1 big gold fish
    2 Chineese alge fish

    All runs off API Filstar XP-L canister
    Two power heads for proper water rotation

    Have tank for almost a year all fish have being doing awesome fish would swim aggressively nip at each other but always got along swimmingly, now the big bullies my two dark tiger oscars are lathargic show no aggression and swim or lay at bottom of tank. Albino and every other fish seems fine.

    At first I thought it was due to recent wanted change about a week ago when I did my water test
    ph 6.6
    high range ph 7.4
    ammo 0.25ppm
    nitrite 0.25ppm
    nitrate 5.0ppm
    Water temp was high 70s low 80s degrees Fahrenheit
    I know those aren’t ideal conditions and am working to get that back in order

    So my initial thought was new tank syndrome I water changed and had my ammonia nitrites and nitrates out of whack was the reson they were acting weird so I added a nitra zorb pack to my canister filter and introduced a fan to cool water to 73 degrees nitra zorb claims to reduce all nitrate, nitrite, and ammonia levels to a safe condition so I figured water should be getting better

    But my two dark oscars fluctuate in this lathargic behavior gain color float at top lose color sit at bottom and only the two dark oscars do this sometimes appear to be dead until I push them to swim.
    Okay so long story short how do I know if they are sick not that I don’t mind them being peaceful to the other fish but I rIsed these fish since they were tiny, they have always been the bouncers of my tank now they are just laying round and turn from pale aitting at bottom to dark sitting top of water?

    I think it might just be the water temp but I guess I should do a more current water test

    • TankTerrors says:

      I have been away, hopefully you were able to figure it out. You shouldn’t have any nitrite or ammonia though, keep that in mind.

  • Cameron says:

    I just got my oscar fish and they are about 2 inches long and during the day they lay at the bottom of the tank and wont eat but at night when the light is off they are active but my main concern is they wont eat what do i do?

    • TankTerrors says:

      They may still be adjusting or the lights may be too bright for them. 2″ is still a baby so it may adjust over time.

  • N.SARVESH says:

    i have two OSCARS in a tank in which one of them is doing good but the other one is laying at the bottom itself not eating the food akso please help me on this.

    • TankTerrors says:

      It could be a number of things, if you have two and no other fish the one laying may be getting bullied. So you may need a divider or another tank. They tend to work best in multiples instead of pairs if you want more than one. It can work for sure as a pair but sometimes you end up with a bully though.

  • sagar says:

    I have a 75 gal tank with 1 7 inch Oscar., 1 12 inch a rowan, 6 parrot 4 inch,2 cebrum 4 inch, 1 buttikoferi 6 inch,1 jaguar 6 inch,1 shortbody,2 yoyo loach,1 ornate bircher, 1 pleco 8 inch, 1 salvini 4 inch..which filter is best for my tank

    • TankTerrors says:

      The largest you can afford mate. That tank is decent sized but pretty over stocked. You need to be doing water changes a few times a week. I would suggest at least double the tank size. A monster filter won’t even keep up with that much load in a 75g.

  • gregory gray says:

    I have a 75 gallon fish tank with one re Oscar for the first time I saw her laying on her side but what I did is I took one of her rocks out could that be the reason for her to be lying on ground

    • TankTerrors says:

      Oscars are very temperamental. It could be a number of reasons. If they have clean water and are fed it is usually just a phase or adjustment time. I have had them be grumpy for weeks or months and then be just fine.

  • miguel says:

    I could use some help..
    I have a 250 gallon tank. I have four albino oscars measuring 10-12 in each. I also have a pleco, about a foot as well and two Raphael catfish measuring about eight inches and usually hidden. They have all been tankmates for about ten years. No new changes. Same fifty percent water change once a month that has never changed. I recently had one of the larger cichlids start laying on its side on the bottom, been doing it for about a week now, and refuses to eat. I don’t know if its about to lay eggs, or if it’s too old to lay? or if the fish is getting old? There’s no indication of illness or distress. Water tests are very low in nitrites and nitrates, nothing out of the normal, water quality is great. Could use some answers super please.

    • TankTerrors says:

      Well it is most likely just a stressed fish or he is just getting old and has an issue. That is very old for a captive fish so you have done well. If you have clean water then the only thing I could suggest is moving that one fish to a new bare tank with no light – a quarantine tank of sorts but good sized. Then it will eliminate any other fish or things in the current tank that may be bothering it.

  • I have a 1 1/2 inch and he doesn’t eat all food givin within a 2 min period should I be concerned

  • Tina Withrow says:

    I recently bought my daughter and I oscars. She has 2 and I have 2. Her 2 constantly lay on the bottom TOGETHER. Almost on top of each other. They are very young. They are not eating either.
    My 2 are swimming all around and are eating.
    Would hers me a male and female?
    She doesn’t have alot of plants in hers, would that matter?

    • TankTerrors says:

      The plants will make them feel a bit more secure but it shouldn’t make a massive difference. Plenty of people keep them in bare tanks. It may just take them a bit longer to feel comfortable. Oscars do love to pout.

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