Frequently Asked Questions about Oscar Fish Cichlids
Welcome to our Frequently Asked Questions section. You will find the answers to many commonly asked questions regarding the keeping of Oscar fish, plus fish keeping in general. If you don't find the answer you are looking for then please visit our community forum where you are sure to find someone who will help you with any questions you may have.
I've noticed over the years that some people get confused between "Oscar" and "Cichlid". People often ask what the differences are between an Oscar and a cichlid. It's an easy mistake to make, especially if you are new to fish keeping. Okay, for starters cichlid, (pronounced - sick lid) are actually a family of fish to whom the Oscar belongs. So if you say you are keeping cichlids, that could be any of over 1000 species of cichlid. So you can see that asking the difference between an Oscar and a cichlid is impossible to answer because actually, an Oscar is a cichlid.
If you still can't quite grasp what I'm saying then take a look at the different species of dogs that you get. If you asked someone what kind of dog they had and they replied "Terrier" you would almost certainly ask what type of Terrier because you would probably know there are different breeds of Terrier. Look at cichlids in exactly the same way and you can't really go wrong.
We wouldn't recommend that complete newcomers to fishkeeping go out and buy an Oscar, that would be a very unwise thing to do. However, if you've been keeping community fish for a while and you fully understand how to look after fish properly then an Oscar shouldn't pose too much of a problem as long as you understand exactly what requirements they need
This is one of those questions that is perfect for the "FAQ" section. You would be surprised how many times people use the search term and find our website. The simple answer to this question is ABSOLUTELY NOT.
DO NOT attempt under any circumstances to keep an Oscar fish of any size in such a small aquarium
About the Oscar Fish Cichlid. ..
Oscar Fish normally reach sizes between 10 and 13 inches in a home aquarium. However, it's possible for an Oscar to exceed this size occasionally, but it is a rare occurrence
If you're in the position where you can have any size tank then obviously you could fill it with as many Oscars as the tank permits. Obviously, most of us can only house small aquariums at home. If your aquarium is no bigger than 75 gallons then that limits you to one adult Oscar. Once you get to 100 gallons + then you can start thinking about having two Oscars. Three or four Oscars would require a sizeable tank well in excess of 200 gallons. A tank of this size would probably need to be custom-made for you. However it's vitally important that you remember that the size of the aquarium is only half of the equation, filtration would need to be increased considerably once you start keeping two or more Oscars.
If you are thinking about getting an Oscar Fish and already have an aquarium then it's vitally important that you know exactly how much water the tank holds. There are various mathematical equations that you can use to work out exactly how much water it holds. However, using our simple calculator, you can enter in the dimensions of your aquarium and it will tell you exactly how many gallons it holds, either in US or imperial gallons. Before you measure your tank, remember that the water may not come all the way up the front of the glass, so when you measure how high the aquarium is, measure up to the level of the water. Even if you add on an extra 1 inch in height, that will make it seem like your tank holds more water than it actually does.
Assuming that you look after your Oscar properly, maintain water quality on a regular basis and feed it on healthy food, your Oscar should live for 10 years quite easily. However, an Oscar Fish could exceed 15 years
The directions on fish food normally tell you to feed your fish several times a day and for a given amount of time. Personally I don't take much notice of these directions as the manufacturers are just trying to make you use as much of their product as possible. In the wild fish will not have a reliable food source like they do in your aquarium, they will have to go looking for their food which may result in them going hungry for a day or two. In the dry season when the waters recede fish can often go without food for weeks.
Most people feed their fish every day, sometimes more than once a day. An adult Oscar Fish does not need to be fed on a daily basis, you could quite feasibly feed your fish every other day, or even three or four times a week and your fish would be perfectly okay. I must emphasize that baby and juvenile Oscar's should be fed on a daily basis until they reach adulthood.
I normally feed my fish as much food as they can eat in two or three minutes and then I stop. I don't put a handful of food in, I introduce five or six pellets at a time and I wait until the Oscars have eaten these and then I introduce a few more. If all the Oscars are about the same size I leave it up to them to compete for the food as I believe this keeps them active and alert.
For information on what to feed your Oscar, please visit the link below for an extensive article on various types of food you can give your Oscar fish
Yes, you can breed Oscar Fish in your home aquarium. However, we would never recommend undertaking the breeding of Oscars unless you have somewhere to offload the babies. We highly recommend reading an article on breeding Oscars
How to breed Oscar Fish..
Oscar Fish live in tropical waters so their water must be kept warm at all times. We would recommend water temperature be maintained between 26 and 28°C (78-82°F) if possible. Water temperature shouldn't be allowed to exceed 30°C (86°F) for too long, and drop below 21°C (70°F)
I would recommend using an electronic that will give you very accurate readings. Avoid glass thermometers that stick on the inside of the glass as these will more than likely get broken.
The pH of your aquarium water should never be adjusted unless you absolutely know what you are doing. Therefore a pH of between 6.0 & 8.0 is perfectly okay for your Oscar Fish. If you are finding it hard to maintain pH levels then please seek advice on our community forum
Anybody who keeps aquarium fish should be in the possession of a
It's not fully understood why Oscars, or fish in general yawn. We do know that fish don't yawn to introduce oxygen into their body. There are two theories to as why fish yawn, it could be to remove irritations from within their mouth and throat, but it is more likely due to water conditions, either high nitrates or high water temperature.
People often panic when they see their Oscar shaking its tail and sometimes its body, they think there's something wrong with the fish. Worry not, fish communicate by shaking their tail. It could be a case that the Oscar is trying to attract a mate by shaking its tail. If you have two Oscars then you may observe them rubbing against each other whilst shaking their tails. If this does start happening then you may be lucky enough to have a breeding pair.
When in doubt, get the water test kit out, test for ammonia, nitrite, nitrate and pH.
But honestly, I've never experienced any problems when my fish have started shaking their tails.
We normally advise people against feeding live fish to their Oscars as we believe it really isn't necessary since there are plenty of foods available that provide all the nutrients and goodness that your fish requires. However, if you are absolutely adamant that you want to feed live fish to your Oscar then it's very important that you only feed fish that you know are disease-free. Therefore you must not buy goldfish that are renowned for carrying parasites and disease. If you buy fish from the fish store them it's always a good idea to quarantine them for a few days, just to make sure that they are not harbouring disease or illness. If you can breed your own life feeders then that is obviously the best option because you then know where they come from and how they have been bred.
Yes, vegetables are actually a good addition to an Oscars diet. Whereas vegetables are not a necessity, they are thought to aid digestion. If your Oscars will accept vegetables then peas are an excellent choice as they can often help if the Oscar suffers from constipation as they do occasionally. You can use peas straight from the freezer, there's no need for any preparation, just let them thaw before putting them in the tank.
It may be that they don't like a certain type of food, it is not uncommon for Oscars to completely despise some type of food. Try different types of food and see if they eat. If your Oscar refuses to eat any type of food, even after a few days then please consult us on the community forum and we will try and help further.
Aquarium water should be tested on a regular basis as poor water quality can have a serious effect on your fishes welfare. Test your nitrate before a water change, this will give you an indication of how much water needs to be replaced. Nitrate shouldn't exceed 40 ppm. Ammonia, nitrite & pH tests should be carried out every now and then just to keep a check on things. If your biological filter is healthy then ammonia and nitrite should never exceed 0 ppm.
If you are a responsible fish keeper then it is very important you have an at your disposal so that you can test your water any time of the day or week.
We don't recommend feeding animal meat to your Oscars because most animal meats contain saturated fat which can cause a problem with the fishes liver. If you want to feed meat to Oscar then choose lean meats. Our advice would be to purchase ready prepared beef heart from your fish store as this is lean and doesn't contain a lot of fat
Water changes are an integral part when keeping fish in an aquarium. Failure to carry out adequate water changes will result in poor water quality which can make your fish more susceptible to disease and even death.
If your aquarium is big enough, stocked properly and you feed your fish sensibly then nitrate levels shouldn't reach high levels within a weekly period. In reality you shouldn't really need to change any more than one third of the water each week. However we all know that overstocking aquariums is quite common and therefore nitrate levels will be that much higher at the end of the week. In these cases water changes will need to be slightly larger. It's quite easy to work out, if you test your water for nitrate and the readings are 40 ppm, it will take a 50% water change to reduce the nitrates back to 20 ppm.
If you have tested your water and your nitrate levels are extremely high level instead of carrying out a huge water change, you might be better off carrying out several smaller water changes over a few days. Sometimes fish that have been housed in an aquarium with high nitrate actually get used to being exposed to these high levels. If you were to suddenly change a massive amount of water all at once, it has been known for fish to become shocked and die. I don't think this is a common occurrence but it's something you should be aware of.
It is important that you carry out a nitrate test properly and read the instructions fully. This video will show you exactly how to carry out a nitrate test
Using buckets to change water in a large aquarium is very time-consuming. However, there are products you can get that will make the water change a piece of cake. One such product is called the and is extremely popular amongst many of our members.
Having the correct filtration system on your tank is absolutely paramount. Your filter will remove solid waste and the dangerous toxins that are produced by your fish. The Oscar fish it is a large Cichlid that will create a large bioload. In its simplest terms, the bioload is the amount of pressure that is put on your biological filter through ammonia that is produced through a fish breathing, in its urine and solid waste. If you haven't got an adequate filtration system then dangerous toxins will just keep building up until the inevitable happens, your fish dies. So the filtration system you install on your aquarium needs to be able to handle the amount of ammonia and waste your fish will produce.
We always recommend installing lots of filtration, normally double the amount of filtration the tank is rated for. This may seem like a little bit of an overkill but believe me, having lots of filtration will benefit your fish and help keep your tank a safe place for your fish in the long run.
The two types of filter we would recommend are the external aquarium canister filters, or if you want to have the absolute beast of all filtration systems, install a sump filter. Both these type of filters can hold large amounts of biological and mechanical media filtration.
There are lots of different makes of filtration on the market, however one of the two most popular are the , and the which are very well respected and used by millions of fish keepers around the world
Here is a small list of biological and mechanical media that is commercially available and that works extremely well in a sump filter
Scrubbies - these are probably the cheapest option if you are looking for biological media for an aquarium sump filter, scrubbies are made for cleaning dishes, however they make excellent biological media for your sump filter as they have a large surface area for bacteria to grow on. Three or four packets of scrubbies will give you an enormous amount of biological filtration. The only disadvantage with this type of media is it will collect a lot of debris and dirt so you will need to clean them every few weeks.
Bio Balls - this type of media is absolutely superb, slightly smaller the ping-pong ball and containing lots of little prongs, they have a large surface area for bacteria to grow on. 1000 bio balls will be enough to filtrate several hundred gallons of aquarium water. They are excellent as they never get dirty so you don't have the problem of trying to keep them clean like you will scrubbies
Flocor Filter Media - this media is what they call an open cell media and resemble small segments of plastic tubing. The advantage with this type of media is they won't get clogged with debris and dirt so you never have to worry about water flow being restricted
Alfagrog - this media is extremely porous and resembles small pieces of rock. Although extremely efficient as biological filtration, this will eventually become saturated with debris and dirt. My advice when using this type of media is to put it in media sacks so that when you want to clean it, you simply remove the whole sackful of media
K1 Media - this is self-cleaning media, however, it needs to be aerated properly. Once moved by continuous column of air it will give maximum effective removal rates of ammonia & nitrate. However at nearly £70 for a small sac, it is very expensive
Filter Media Brush - these are not really meant to act as biological filtration, filter brushes make excellent mechanical filtration and when placed at the very front of your filter where the water enters will catch and stop debris from flowing through the sump filter and clogging up your biological media
Japanese Matting - Japanese matting makes superb mechanical filtration and will collect large debris. If you've got a large sump filter then feel free to use several layers in one chamber. Just remember that eventually matting will become clogged with debris and will need to be cleaned.
Filter Foam - this is also mechanical filtration, however it is slightly finer than Japanese matting. I like using it just before the biological filtration as it will filter out the final bits of solid debris that makes it through the brushes and Japanese matting. Again, foam filtration will become clogged and will need to be cleaned every few weeks depending on stock levels.
Exactly how long it takes for bacteria to completely die off it is hard to say, but from my own personal experience I have switched my sump filter off for up to two hours and I haven't experienced any problems.
I have heard of people switching their filters off at night, or during the day to cut down on the noise. This is something you must never ever do, the filtration system must be kept running at all times and only ever switched off for cleaning. Never let the media dry out for you will lose the bacteria.
New evidence has suggested that beneficial bacteria that live inside your filters can last a lot longer than we ever thought when deprived of oxygen or a service to live on. Having said this, until there is overwhelming evidence to support this fact we would recommend that you do not turn your filters of for too long at a time.
Hole in the head disease (HITH) affects many different types of cichlids including Oscars. It normally occurs when fish are kept in poor conditions and fed an unsuitable diet.
Symptoms are often small holes developing around the head region. If left untreated, these holes will get larger and deeper and maybe become infected.
Hole in the head disease is both curable and preventable. If your Oscar starts showing early stages of hole in the head disease, increasing tank maintenance and keeping your water in extremely good condition can often clear up early stages of hole in the head disease. Very severe cases may well need intervention with a good . However, regular water changes and a healthy diet are thought to be the main key to preventing an Oscar from developing HITH Hole in the Head Disease in Oscar Fish...
The simple answer to this question is yes, of course, you can put plants in your Oscar tank, however, don't be surprised if the Oscars uproot them, or even just completely rip them to pieces. For some reason Oscars seem to take a dislike to plants and nearly every person who keeps these fish will tell you that they are not successful in keeping the two together.
The Amazon Sword is probably the most successful plant I have ever managed to put in with my Oscars. They are native to the Amazon River so will look authentic if you want to set up an Amazon theme aquarium.They are a fairly hardy plant that will not die on you overnight. Even though the Oscar may be able to operate one of these plants, they can be rerooted fairly easily.
If you keep plants remember that you will have to look after them in much the same way as your garden plants. If you really want plants then you could try artificial aquarium plants. Some of these are quite realistic and obviously fairly tough. The Oscar will still uproot them and they will also need cleaning every now and then because they collect algae quite easily. I have tried keeping plants on various occasions but I gave up a few years ago because it just isn't worth the bother in my opinion
One of the most common infections fish pick up in an aquarium is called "White Spot" or more commonly in the USA, "Ick". White spot is perfectly treatable and if you catch it early enough won't cause any problems whatsoever. We have a well written article on treating white spot that will explain everything you need to do to cure your fish of this parasitic infection
There are a lot of available if you need them
Treating White Spot...
Gravel is cheap and readily available from fish stores and garden centres. You can often get a large 20lb bag of gravel for as little as £5. When you buy gravel it will need to be washed thoroughly as it's normally extremely dirty. Gravel is very good at masking debris and dirt such as fish poo. However, solid waste has a tendency to find its way underneath the gravel which if left could contribute to poor water conditions. With the aid of a gravel vac, you will need to give the gravel a thorough clean which is often quite time-consuming, especially if you've got a big tank. If you are planning on putting plants in your tank then gravel is probably the best option as plants don't really like sand.
Sand comes in lots of different colours and can look absolutely stunning. Sand can be obtained fairly cheaply from garden centres, however, some types of different coloured sand can be quite expensive, as much as £12 for a 10lb bag. Solid waste doesn't tend to get embedded under the sand like it does with gravel. You'll find that the waste sits on top of the sand where it is much easier to remove with a gravel vac. One drawback of having light coloured sand is dirt such as fish poo can look rather unpleasant. Pleco waste is particularly unsightly so if you have got fish that are notorious for producing lots of waste, it might be an idea to opt for a dark coloured sand where the dirt isn't so obvious.
A water conditioner is used to remove chemicals such as chlorine and chloramine from your tap water. The chemicals that water companies put into the water to remove bacteria are harmful to fish so you must use a water conditioner every time you carry out a water change. Most water conditioners neutralise chlorine and chloramine on contact so you can add the water conditioner to your tank and then top it up with tap water after a water change. If you have got a large aquarium and therefore carry out large water changes you would be wise to shop around for water conditioners and find the best value for money. Some water conditioners don't really go over a long way, for instance you may have to use 25 mL for every 10 gallons of water, obviously this means that a 200 mL bottle is not going to last very long if you are changing 100 gallons of water. I use a water conditioner called which goes a long way, you only have to use 5 mL to treat 50 gallons of water. 250 mL of Prime will treat something like 1000 US gallons of water. So for someone like me who changes 100 gallons of water every week, a 250 mL bottle of that costs £11.95 will last me a few weeks.
If you're in the UK then you're probably not very far away from a fish store. However I know for certain that some people living in North America often live hundreds of miles from the nearest fish store. Obviously it's not practical for them to buy things as the journey would be so long and cost a lot of money. People often ask me where they can buy things such as test kits, filters, heaters etc. In my opinion the very best place to buy your aquatic products from is eBay. To try and help you get what you need I have included various links below, each link will take you to a product on eBay. The links are all setup using geo-targeting which will ensure you are taken to the correct eBay for your country. Unfortunately some countries are not included in the programme so obviously you may have to find out if you can purchase from eBay in other currencies that are not your own currency.
I will include various links below that relate to products that you will need if you are keeping tropical fish. Simply click on the link, you will then be taken to your eBay.
- these treatments should always be used if you are changing water in your aquarium. Chlorine can be very dangerous if the fish are exposed to it for too long.
- every fish keeper should own the water testing kit that enables them to instantly check whether their water is safe or not.
- cloudy water can be cleared up without having to treat the water. However, in some circumstances treatments may help
- hole in the head disease can be a serious condition and must be treated immediately. There are lots of different treatments available. Before buying any treatment, we would advise you to seek advice on our forum
- this is not a product that I use myself, however some people like to use it and we are not here to tell you that you cannot buy these products
- some foods that are meant for fish fry come in the form of liquid
- we always recommend feeding a good quality pellets to Oscar as its primary food
- yes you can buy live food from eBay, probably best not to try and ship it to another country as it probably will not be allowed
- filters are not cheap, however you can often pick up fantastic bargains on eBay
- it's important that you get the right size heater for your area. Lighting isn't as important, however if you keep plants or want to emphasise the colours of your fish then choose the correct lighting system. EBay has a vast array of different lighting systems that should suit your needs
- there are too many treatments to list on this page, however using the search term "Fish medication" will give you a nice variety of different medications that can be used to treat aquarium fish
- if you want more than sand and rocks in your tank then you may like to put some ornaments and decorations in to make it look nicer