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Are You Ready for the Big Fish?

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We've all seen them. Cute little Oscars with big puppy dog eyes, staring woefully at us as if to say "take me with you please". I fell in love with my first Oscar when I was about 10 years old. It lived in a window display tank of a fish store inside a shopping mall where I would ride my bike to. I couldn't wait to get there and stare at the giant creature that I knew I could never own. I actually tried to talk my parents into letting me have him but thank God they had the good sense to say no and I settled for my first 40 liter tank instead. The seed was planted, however, and what grew was a passion for the big South and Central American cichlids that continues to this day, over 25 years later.

I often think of what would have happened if I had been allowed to have such a creature at that young age, and with no prior experience. No doubt I would have made the same mistakes that so many others make when they take on fish that they are not prepared to care for. The majority of large growing fishes such as Oscars or Bala Sharks that are sold today in stores such as Walmart or even your local mom-n-pop fish store, end up dead or traded back in when their size and care has made them an unmanageable proposition. I do not have any scientific data to back this up, but I would confidently estimate that less than 1 in every 10 Oscars sold in the US today will ever see adult size. The most common maladies that do in these magnificent creatures are disease and damage resulting from poor water conditions and overcrowded tanks. My first cichlid tank when I was in my early 20's ended in complete disaster, at which point I began to ask questions and I learned that you can't fit 10 Jack Dempseys and 6 Convicts and 2 Oscars in a 200 liter tank and expect good results.

So you've seen the eyes, and you've heard the stories of these big fish acting like pet dogs, letting you pet them or playing with a ball. Whatever the reason, you have the desire to start a tank of large aggressive cichlids. Or maybe it could be that you have already bought the fish and things aren't going right, and you are looking for answers why. Hopefully you will find something here that can help you avoid the kind of mistakes that I made with my first Cichlid tank. Maybe even something to help you make some corrections to your existing situation and assist in pulling your project back towards success. Although I mention Oscars and Cichlids most often in this article, most of this is basic information that can be applied in almost every other situation where you are considering keeping a large fish in an aquarium.

First of all, there are some very important questions that you need to ask yourself before you buy the fish or decide what to do with the ones you have. If you are of the mind-set of "I can just trade it in when it gets too big", or "I just want to get it big and bad and watch it kill something", then you might as well stop reading now and save yourself the time. I wrote this article for those who share my passion for keeping these animals as true pets. Someone who is serious about achieving long-term success, and has some basic knowledge of what they are getting themselves into, will hopefully find it useful. I have ranked these considerations in order, starting with what in my opinion is the most critical. Not all will apply directly to your situation and I'm sure there are others that could have been included.

  •  Am I prepared to care for this fish for the next 10 years?
    A lot can happen in 10 years, and obviously there may be situations that come up where a pet of any kind would have to be parted with. However, I find this to be a very sobering question to ask myself whenever I am in a compulsive mood and there is a fish staring me in the face and I'm just sure I have to have it. The reality is that, if properly cared for, most large Cichlids can live to be 10 years old and many have been reported much older. In my opinion, it should be our goal to think of and keep these large fish as pets, which in and of itself implies that we intend to allow this animal to stay in our care for its entire life span. From my own experience, I have gone through periods where my interest in the hobby waned and I put it aside for a while. It happens. If you see from your past experience that your attention span is probably only going to last a year or so, pick something else other than large cichlids. One other consideration that comes to mind is the importance of knowing the habits of these fish and asking yourself if it is something you will grow tired of when the novelty wears off. For instance, one of the most endearing traits of large Cichlids is their insatiable desire to dig and re-arrange the tank to suit their own taste. If you have it in the back of your mind that sometime in the next few years, you would like to turn that big tank into an Amano-style underwater garden, forget about it. Most likely scenario is that, with the possible exception of some floating plants, this tank will resemble a barren moonscape for the next 10 years.

  •  Can I provide this animal with the space that it needs to grow and achieve its adult size?
    I myself have been guilty of telling myself "I'll just get the fish now and when the time comes I'll get that larger tank I've always wanted". The problem is that when the time comes, more often than not, things have changed and we either can't afford it at the moment, or we ran out of space, etc. Meanwhile, we have a fish in our small tank that we know doesn't have enough room to grow, so back to the store it goes. I will not touch the whole issue of fish growing to the size of their tank here since I have as of yet to take the time to study the scientific evidence either way, but I do firmly believe that a fish will never reach its full potential if it spends its most formative first year in a tank that is too small for it. If we plan ahead and buy only fish that we have current capacity to house, we eliminate the need to have to worry about that issue. All of this is complicated by the fact that there is no rule in place to tell us what size tank to house a certain fish in. Many arguments ensue over what should be the minimum tank size for a given fish; most often Oscars are the center point of the discussion. The safest way to get around this issue is to buy the largest tank you can possibly afford, and then work down from there when deciding what fish to put in it. When you go the other way, buying the fish first with the intentions of letting it live in your small tank for a while, you will invariably find yourself asking what the minimum tank is that you are now forced to purchase, in order to keep this fish that you have become attached to. Meanwhile, its development may or may not already be stunted to some degree. Hand in hand with the size issue is the next question:

  •  Do I have enough filtration to handle a project like this?
    Obviously the first question that would have to be answered is what size tank do you have. There is no hard and fast rule about how much filtration is required per fish or per tank size, but I like to shoot for a filtration rate of no less than 8x to 10x per hour, water turnover. This means that your filter(s) remove and replace the water in the entire tank 10 times every hour. For example, an Aqua Clear 500 moving 500 gallons per hour would turn a 50-gallon tank over 10 times per hour. Now keep in mind that this is a lot of filtration, but don't get feeling lazy and expect it do the entire job for you. Rigorous vacuuming is still required, because much of the fish waste will become too heavy for the filter to lift. One thing that is certain is that, with the amount of waste and ammonia that these large creatures excrete, you need to have a balance of excellent mechanical filtration, combined with enough surfaces within your filter to grow a huge and healthy colony of nitrifying bacteria. If you don't already have a clear understanding of what the nitrogen cycle is all about, read up on it and make sure you understand it, because one bad move with one of these tanks can spell disaster. As we push the envelope of reason when it comes to how much ammonia our bacteria colony is handling for us on a daily basis, a sudden loss of that colony due to careless replacement of too much filter media, or a filter that dies, can cause toxic levels of ammonia very quickly.

  •  Can I maintain a rigorous maintenance routine and for how long?
    This could actually be the most critical question because it is so important to the long-term health of your fish. It is not a stretch for me to say that the vast majority of aquarium diseases can be avoided entirely by a quality maintenance routine. If you get any one thing from this article, let it be this: Don't take maintenance lightly! It is not easy to condition ourselves to perform this task, week in and week out for a period of years. If you are looking for a tank setup that you can set up and ignore for weeks or months between water changes, do not choose large Cichlids! If you know that you will be heading off to college and are thinking that Mom and Dad will take care of the tank for you, do not choose large cichlids! From my personal experience, I know that things can get out of hand very quickly if we start being lazy with our maintenance routine. The main problem that will arise, comes from the by-product of the fish waste: nitrates. As nitrates accumulate in the water, they will eventually reach a level where they start to become toxic and stressful to the fish. Although there is some debate as to the actual level where nitrates become toxic, I tend to believe in the widely accepted 40 ppm as the magic number, and I use this as a basis for my maintenance routine. There may be other methods, but this one is measurable and I use it with great results. So, to me, the most important tool to a keeper of large cichlids (other than their water changing gear) is a nitrate measuring kit. I personally prefer the dip stick type, because it's quick and easy. Your goal should be to maintain less than 40 ppm of nitrates, without having to change too much water at one time. This is going to be greatly affected by the size of fish being kept and the size of tank they are being kept in. For instance a 30 cm Oscar that is being kept in a 200 liter tank would probably require 50% water changes weekly, whereas the same fish if moved alone into a 1000 liter tank might only require 5% weekly, or more likely 10% biweekly. These are approximate numbers, of course. My point is that the larger and more lightly stocked the tank is, the less maintenance you will have to do. The thing to remember with nitrates is that they will have a cumulative effect, so if you miss or skip a couple of weeks, you are going to have to do more than your normal changes to catch back up. What I find very especially important when dealing with large fish, is to set up a water change schedule by testing for nitrates, then sticking with it. If you find out that you have to change 50% of water a day to keep your levels under 40 ppm, then so be it. This is an extreme example of course, but not unheard of. It is most likely that this level of waste would overwhelm the biological filter and there would be bigger problems to worry about, such as ammonia or nitrites. I know all of this sounds overwhelming, but it's really not. It is just part of the commitment that needs to be made before taking on a tank like this. Once you get into a regular routine of making a specific change on a specific day, such as 50% every Sunday, it gets easier. Remember to vacuum vigorously when changing water, because every piece of waste that you vacuum up is one less piece that will be broken down and converted to nitrates.

  •  What do I really know about this particular fish and is it compatible with this other fish?
    This subject always reminds me of the story of the boy who goes in his local fish store and asks the man "What is the meanest, nastiest fish in the entire store?" After carefully selecting his fish, the boy then asks, "What can I put with him now?" If you are even slightly unsure of the compatibility issue, do your homework ahead of time. If you have decided to go ahead and take on a mixed cichlid tank, don't assume that you already know all there is to know about a particular species. The Internet contains a wealth of information about almost any species you can imagine, so use it. Even after all this study, there is still no guarantee of immediate success. What you must be prepared for is that when you are talking about Cichlids, although temperaments vary from fish to fish, they are generally territorial and aggressive, period. It is their nature. This behavior is instinctive and cannot be "unlearned". The level of aggression will be directly proportional to the amount of space that you provide. Your best hope is to provide every occupant of the tank with enough territory to establish its own space. Some species that are known for extreme aggression are said to become quite mellow and docile when provided with a huge tank. Others will have a built-in bad disposition, and there is nothing you can do about it. Don't learn the hard way that some of these fish will simply not tolerate tank-mates period, and will end up a lone fish in a large tank. Sometimes all we can do is try to avoid known situations where a less aggressive species is not going to stand a chance. At the very least, you will need to give them all an equal opportunity to claim territory by adding them all at once while juveniles and growing them up together. This is no guarantee of success however, as some species such as Managuense's or Red Devils usually don't really develop their nasty disposition until they get approximately 10-15 cm in length. One of the worst things you can do to a new fish that is being added to an existing "community" of cichlids is to simply plop it in the tank and make it fend for itself. It is better to remove all of the fish, break up territories by re-arranging the tank, and finally put them all back in together. Another situation that needs to be avoided is the mixing of species such as African and American Cichlids, where their entire style of fighting is different. For instance, you can go from the hit-and-run, defense-of-territory, live-to-fight-another-day style of the African Mbuna to the lip-locking, kill-because-they-seem-to-enjoy-it Central or South American Cichlid. A mismatch of these styles will usually end with the death of one of them. By the same token, one should avoid the common mistake of thinking that, simply because a fish grows large, it will be able to take care of itself in a tank of other large fish. Nothing could be farther from the truth. A full grown Bala Shark at 36 cm, or several full grown Frontosas at 40 cm, are no match for the fierce nature of even one 15 cm Cuban or Green Terror.

  •  Are my water parameters close enough to what is required by this fish?
    At all costs, you will want to avoid getting yourself into a situation where you have to tinker with your water parameters with every water change. With the sheer volume of water that is used to house one of these animals, I can assure you that you will quickly tire of a costly and time-consuming maintenance routine that involves altering your water parameters. I can also confidently assure you that with every existing water parameter available, there is a large cichlid that will work fine in it. For instance, if your water is hard as a rock, you may want to go with large Africans such as Frontosas or Livingstoni's. Moderately hard water is preferred by Central Americans such as the Red Devils, and their beautiful cousins the Trimac. Soft neutral water is the favorite of the majority of South American cichlids, so pick what you like. The point is to make sure that you do your homework and pick a fish that can easily tolerate YOUR water and work around that. You don't want to get into the trap of adjusting your water to fit your fish. It can be done, but usually not for long.

  •  OK, I bought a tank large enough for a small whale, now I've got "Empty Tank Syndrome"?
    This is a VERY common problem. The fact is that one small Oscar does not visually fill up that large tank that we just spent a fortune on. We are usually overcome at this point with the desire to add tank mates and fill up all of that empty space and get our money's worth. However, if we do this then we have really come all the way back to the second question of "Have I provided the space necessary to allow these fish to grow to adult size?" Sadly, the answer will almost always be no, and one or more of these fish are going back. For those of us who are less than patient people, there is no easy answer to this one. One suggestion that I have employed myself in the past is to put in a group of "expendable" fish, such as Danios or Guppies, for flash and color and activity. The other thing that this allows you to do is to see some of your new pet's predatory instincts develop and be put into action, as the feeder fish are dealt with along the way. I understand that this might be objectionable to some, but chances are pretty good that if you are seriously considering keeping large Cichlids, you are already aware that feeder fish are considered a popular food source. I personally feel that it is a little silly for one to consider a goldfish or guppy OK to be used as a feeder, but not a danio or a tetra. What really matters here is whether you're using captive bred fish as feeders - which is OK, or wild caught ones - which is not. Usually it is more of an economic difference than anything. The point is to be creative, and don't give in to your urge to buy 10 baby Oscars unless you are hoping for a pairing, which brings me to my next question.

  •  What are my goals here, do I want these things to breed?
    Very important to have this all figured out before you start with Cichlids. If you buy two or more of any of the same species, you have to assume that they might breed. One of the very things that make Cichlids so special to those of us who keep them is their natural parental instincts. Unfortunately it also makes for a disastrous situation if you have created a "community" of these fish, and then two of a given species decide to become a pair. The result of this situation, depending greatly on the temperament of the species and the size of the tank, is anywhere from simple claiming of a territory and defense of nest, to vicious attacking and killing of any and all other inhabitants. When fry are born, Cichlids are generally excellent parents and guard them well, but even under the best of conditions, you will lose most of them to tank-mates if they are not moved. If you have planned for spawning and are hoping for a strong healthy pairing, the best method to use is to start with more than six juvenile fish and allow them to grow up together, to decide by themselves who will pairing up with whom. Again, depending on the species and tank size, you will likely need to remove the rest of the unlucky fish, or the pair might do it for you. I recommend that everyone try this at least once in their life, as it can be a truly rewarding experience when the cloud of fry emerges and becomes free swimming for the first time. Watching the giant parents gently suck a tiny stray fry into their mouth before re-depositing it back with the rest is truly amazing.

  •  Am I prepared to deal with what and how much these monsters eat?
    Don't say yes to this one too quickly. Some people underestimate just how much these fish actually consume on a given day. On one hand we must weigh our need to be careful and not overfeed, and on the other hand we are often dealing with a gluttonous fish with an insatiable appetite. Another one of the traits that endears these fish to their owners is the fact that they will quickly learn where the food comes from, and will wiggle and seemingly plead with you at most times of the day. Luckily, there are products on the market that, when given regularly, will easily meet the nutritional requirements of your fish. You will still need to supplement the diet with other foods though, to prevent digestion problems and/or a finicky fish. Much information is available to you for your specific fish if you do a little homework. Without exploring the morals or ethics of using feeder fish, I will say that many of us find ourselves in a situation where we maintain a separate tank for the purpose of raising feeder fish for our Cichlids. It is my opinion that this is a far better scenario than using store bought feeders, which can and will carry diseases and bacteria that you really don't want to introduce to your fish. I personally do not use feeders often because of this reason, and the fact that almost the exact ingredients and more can be found in commercial Cichlid food products. This is just one more area where a little thought and consideration ahead of time can help keep your new pet healthy.

    Hopefully you were able to get something from all of this other than a lecture. I also hope that you'll share my passion for the big creatures. The bottom line that I tried to get across is: don't take on a commitment like this if you are not serious or if you don't fully understand the level of responsibility required. There is a Bay Area fish store that I visit from time to time, and it was actually a major part of the inspiration for me to take the time to write this article. As I walk down the row of tanks, I always look up at the top row. Way up where you actually have to twist your neck uncomfortably to see them there is a row of tanks, and each of them is usually occupied by a single large fish who was traded in. The majority of the fish are battle scarred and torn looking, and most have evidence of rotting fins. On my most recent trip to this store, the hidden row revealed that it was filled to capacity. Oscar, Green terror, Jack Dempsey, Oscar, Oscar, Oscar, Pacu, Red get the picture. There were others that I didn't even recognize as well. One fish in particular I did recognize, as well I should. He is a Black Pacu and he has been in the same tiny tank for over a year now, since I started visiting the shop. Why the sad story? I want to help you make the commitment to avoiding have YOUR fish become one of the unlucky ones who end up dead, or in the top row.

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