Warning Signs: Early Indicators of Trouble.

Observation is the greatest tool that a scientist possesses, its also the greatest tool that the hobbyist possesses. Observe your tanks frequently, note how each fish behaves while in the aquarium. Often they will give you key insights to how they are adjusting to their new home and they will often also give you early clues when something isn’t quite right. These are the common things to look for, take note of, and possibly act upon.

1.) Fish are Hiding, Gasping, on the Top of the Water:

• Fish gasping at the top can be from one of three causes. The first is a lack of oxygen. This is an unusual condition but can occur if one uses the incorrect dosages of certain algicides from the glutaraldehyde families or have sufficiently stagnant water. It is important that if using a glutaraldehyde family of chemicals such as is found in Seachem Excel that you follow the instructions rigidly. Overdosing can suffocate fish and cause fish death due to a lack of oxygen, effectively the fish drown. However generally speaking if your using the correct dosages most filters allow for sufficient oxygen exchange by breaking the surface tension of the water. If your fish are gasping and you are not using a glutaraldehyde derivative the second cause to look to is readily observable at the water’s surface. If the surface is being visibly broken and you see ripples in it, oxygen exchange with the atmosphere should be sufficient for CO2 to exit and enough O2 to enter without appreciable shortage. Again if the surface water is being broken, then this really isn’t your problem. The final cause is by far the most common reason that fish are found gasping at the top of the water, this cause is persecution. A dead give away here is when the fish are not only gasping but also trying to hide behind line of sight breaks such as sponge filters and HoB filters. In this case the fish are hiding because tankmates are forcing them to the top. This situation will not only continue but it will get worse until the fish has either been killed or harmony is restored. What you have to remember is that fish commonly fight for territories. They drive out all other challengers from the territory they have chosen to defend. These territories can grow as the fish ages and it can also grow when fish are in spawning condition and are thinking about reproduction. In this instance other fish of the same sex are often seen as competitors and treated with hostility.

2.) Bubbles take an abnormally long time to pop:

• This is commonly a sign that something like medication is inside of the tank. Its also a sign that organic compounds have built up to a dangerous level. Usually preceding this you will see a sheen of an organic oil building up upon the surface. If allowed to continue, this oil sheen can interfere with oxygen exchange making it potentially a life threatening environmental hazard that would require direct intervention in the form of a water change in order to remedy.

3.) Acrid smell coming from the tank:

• One of the first things that I learned in fish keeping was when to detect the build up of ammonia. It is commonly described as a very bad acrid smell. Tank water that is mature and healthy should smell like earth, it shouldn’t have the harsh acrid overtones. It should never be something that you have to stop and notice as the wastes should be metabolized by the filter almost as soon as they are being generated. If you do detect ammonia then immediate steps must be taken or you will start to lose fish. So what can be done when ammonia is detected? Very simply the best course of action is a very large water change. While you are cleaning the tank look for dead fish that may be decaying and fouling the water. Next increase the amount of bacteria in the water. When I have encountered this in the past I have used ADA MATURE AQUARIUM BACTER 100. This is an inert bacteria supplement that wakes up when it is placed in water and begin to metabolize excess ammonia and nitrite. If you can’t find this Fritz Zyme 7 can also be used in a pinch. This is a liquid form of the ADA Bacteria supplement and can help you rapidly metabolize toxic ammonia and nitrite and it can buy you time to add additional filtration to the system. I need to stress that this excess ammonia doesn’t get fixed until the underlying load that caused it is addressed. As fish grow, the waste that they produce also grows. As the hobbyist what you need to determine when things go wrong is why it happened to begin with. If your fish have experienced growth it can be an indication that additional filtration is now needed. Thus the underlying cause of the problem can be remedied with the simple addition of extra filtration. Another cause could be overstocking. This is especially true if the fish are breeding and fry are surviving to the adult stage. The waste of the fish as a collective whole could be too much for the filter to now convert. Adding filtration can greatly help as can removing excess fish from the system. Finally if a dead fish was the cause, removing the rotting corpses of fish that have expired is fundamentally important. Filters are designed to convert waste, they really aren’t designed to rapidly break down bodies. Removing the bodies of dead animals and doing a water change can greatly and rapidly increase water quality.

4.) Fish are listless on the ground:

• The first is a water quality issue. Often times when chemicals and pesticides are used in the house they aerosolize. This process can bring these toxins into the tank, in extreme cases this can easily result in dead fish. In this instance where a potential toxin has found its way into the water, obviously if possible remove the source but also address the toxin as best you can. Water changes followed by running activated carbon can help in eliminating toxins rapidly from the water.
• The second cause of fish being listless and on the ground is pH shock. This can occur often in planted tanks where the water is especially soft. In these tanks the dark reactions of the normal photosynthetic plant cycle can cause pH to rapidly fall to extreme levels relatively quickly. This particular problem can be fairly difficult to address in tanks where RO DI water is used exclusively due to the fact that the fish require soft conditions. It is important to note that in the hobby today the vast majority of fish do not require hard or soft water. Most are now what we will refer to as “Aquarium Strain.” This means over the generations that your particular line has been in captivity, the line has converted itself to the hard and soft requirements that they were born into. Thus for the vast majority of fish now, using treated tap water is sufficient. In cases where you must use RO DI a product like SeaChem Equilibrium can be invaluable in preventing pH crashes or other fluctuations.
• The third cause can be that the fish just doesn’t feel secure in the tank that it is in. This could be for many reasons. The first could be a lack of cover at the top. The lack of adequate top cover causes the fish to live in fear and you often find them on the bottom trying their best to get something on the top of them to protect them from predation from things like birds. Many wild fish exhibit this behavior as they do not understand that aquariums are largely bird threat free. Using floating plants here can be a great way of getting them to calm down and emerge from the bottom. Dither fish are another way in which the aquarist can lessen the fear of predation and get fish to emerge from hiding. Extreme caution needs to be used though when employing this method. Dither fish are fish that are typically smaller and for security move in schools together. If a school of fish are swimming above their heads, the other fish usually come out because this is a sign that the area is predator free. The caution in this method is twofold. First there must be adequate capacity to handle the greater excrement load that adding dither fish will cause. The second is that not all dither fish will thrive in a tank of larger fish. Generally speaking the aquarist needs to use fish small enough to have an active school and large enough to not be a swimming snack to the fish you want to bring off the bottom.
• The final cause of fish that are listless and spending a large amount of time on the ground is disease. Often times fish that are suffering from parasites or other forms of illness become very still on the bottom. During times like this you don’t want to ignore what is happening. You instead want to carefully observe and document everything you can. Often times when fish suddenly become lethargic other symptoms also exist such as white spots can appear over the fish. These of course are very important to the diagnosis of what ails your fish and what steps you need to take to remedy the situation. The one rule of thumb for listless fish is that the problem doesn’t go away, it typically just gets worse if left on its own.