You may have wondered if your pond fish sleep, or whether they have teeth. You might also contemplate why fish smell or how much koi cost. We've answered a few questions in this blog about koi: weird stuff you may have never pondered before, or maybe you have...
Do koi have teeth?
Koi encounter a lot of crunchy stuff as they sift through the mud and gravel on the bottom of a pond. An examination of the contents of the stomachs of wild carp reveals a mixture of plant and animal material, particularly crushed crayfish, snails, and worms. For this, koi need teeth to break up the food. They do indeed have rather large teeth located at the back of the throat behind their gill arches.
The teeth are so far back that it would be difficult to reach, even if you stuck your finger in the mouth of a large koi. They don’t use their teeth aggressively or defensively, so you’re safe teaching them how to eat from your hand. Their teeth are used to smash the food items against a boney palate on the upper surface of the throat area.
The teeth of koi come in three pairs, and they constantly develop and shed the crowns. You might be surprised to find these white, calcium rich crowns in the skimmer of your pond! The koi teeth look much like the molars of mammals such as cows and people.
Do pond fish sleep?
Fish do sleep, but not in the same manner as humans. Fish don’t have eyelids, so they can’t close their eyes. Instead, fish catch periods of rest by floating in one place or nestling into a cozy spot at the bottom of your pond. If you watch your fish quite a bit, you might have noticed this behavior from time to time.
How can I tell if my koi are stressed?
Koi show stress by blushing red in their fins and on their bodies. This is caused by a stressful environment, such as poor water quality. It’s their way of showing you that something is wrong.
Why do fish smell?
Fish smell strongly because of amino acids in their secretions and tissues, which is rich in sulfur and very unstable once the fish dies. The amino acids break down quickly into volatile amines like ethylamine, which conveys a strong odor. When you get fish slime on your hands, it begins to decay almost immediately. That’s when you smell ethylamine. Your nose is keen to pick up these unpleasant amines and it typically means that something is spoiled and unfit to eat.
How many times can pond fish reproduce?
Koi and goldfish can reproduce twice in one year. Normally, a koi or goldfish spawns once per year, but there are situations where koi or goldfish may spawn in the spring and then again in the fall if the temperature is unseasonably warm. Goldfish are more likely than koi to have two spawns per year.
How expensive are koi?
In rare instances, some koi have sold for over one million dollars! Many show koi are sold for five figures. A koi’s value is related to the rarity of its pattern, and this is determined by the intensity of its colors and the pattern in which those colors occur. The rarer the fish’s finery, the more the fish is worth. Ultimately, a koi is only worth what someone is willing to pay for it.
Are fish diseases contagious to humans?
There are a few diseases of pond fish which can be transmitted to a human who has an open wound exposed to the water. Various bacteria from koi are also infectious to humans and can be contracted via open wounds. So, the moral of the story is to keep any open wounds clear of the pond water.
Is the correct term for a pregnant goldfish “twit”?
The answer is yes! Over the last 40 years, in Australia and sometimes England, one common reference word for a gravid female goldfish has been some variant of the term “twit” or “twerp.” The proper term for a pregnant female fish is “gravid” with “twit” being the slang version.
If you keep koi or goldfish in the dark, will they eventually turn white?
A lot of young goldfish that start out orange or red will naturally turn white, even if kept in full sun. An example of this is the red cap oranda, which almost always turns pure white. Some fish will lose all their red, simply due to significant stress.
Any fish kept away from full sunlight, will become paler in color. “A red fish will usually turn orange or even a brassy yellow without sunlight,” Fish expert Doc Johnson says. “Kept in the dark, the effect would be more significant. However, the fish would not turn white just because it was kept in the dark.”
Do goldfish really have a three-second memory?
Despite this popular belief, most studies have found the concept of fish having a three-second memory to be a myth. On the contrary, their memories can last as long as three months! Veterinarian Dr. Richmond Loh used levers to train goldfish how to get food, and they remembered these lessons for several months without reinforcement.
There is also a man who trains a goldfish to do various tricks. Although they are easy and quick to train, the fish do not remember their routine for very long. Because they can only be trained when hungry, most training sessions are about 15 minutes long, up to twice per day.
The talented goldfish wouldn’t remember the order of its routine from day to day, but when rewarded for certain behaviors, it could be trained to put on a 15-minute show with little more than finger cues and food as a reward.
Other beliefs about koi
There are a few other beliefs about koi that are not scientifically proven to be true but would appear to hold merit based on the frequency of occurrence. For example, the more a fish costs, the more likely it is to become sick and possibly die, no matter how well you care for it. Of course, this is probably just Murphy’s Law.
And then there’s the old tale that naming your fish will surely increase its odds of developing an illness or becoming prey to predators. It’s quite common to hear a pond owner warn against naming koi. They’ll be able to back up that claim with story after story. At the end of the day, pond fish are a joy to keep. And like anything else, the more you become familiar with fish care, the more you’ll succeed.
For more information on Koi, check out Doctor Eric Johnson on other interesting questions about koi and goldfish. You might be surprised to find what you learn!
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What to Expect When You're Expecting -- a Phoenix Ecosystem Pond!
Welcome to the world of organic water gardening! Unlike lawns and pools, ecosystem ponds in Phoenix are not as common knowledge for most of us. Very few Phoenix natives or early transplants grew up with a backyard pond or knew anyone who had one. And if we did, it’s unlikely that they were practicing organic water gardening specifically.
But why go through the trouble of creating an ecosystem versus just tossing in some chemicals and getting instant results? For one thing, ecosystems are Earth-friendly. There is life and nature in an organic pond, and life will visit that organic water. Isn't there enough chemicals and concrete covering our planet already? Wouldn't you like to feel good about choosing this home improvement option? So, an ecosystem water feature adds beauty to your yard, gives you hours upon hours of entertainment and viewing pleasure, AND you get to feel good about the choice. Oh, and if you have pets, they can safely drink the water - bonus!
The Process of Creating an Ecosystem
Basically, we are working with the same processes in a new water feature as are used in organic vegetable gardening, and even hydroponics systems. Well cared for and properly maintained your feature will provide decades of beautiful, low maintenance, entertainment, and viewing pleasure.
Maybe think of the new feature as a new puppy. “Pond chemicals” (i.e., algaecide) are akin to a rolled-up newspaper or a swift kick. That’s no way to train a new pet! With patience, and proper positive reinforcement, an organic water feature, like a puppy, will develop into a cherished and well-behaved individual. The key is patience, along with using natural products like beneficial bacteria and enzymes, encouraging the "good-guys," and having the right balance of plants, rocks, and fish. This combination creates a closed ecosystem that can be managed easily. Our philosophy has always been KISS: keep it simple, silly!
An Ecosystem IS WORTH THE TIME & PATIENCE IN THE LONG RUN
But here’s what happens right away as the ecosystem in a living water feature is brought to life. Like a new garden, we prepare the foundation: building with natural rocks (to support the zooplankton life), and adding aquatic plants, fish, and beneficial bacteria (just like good soil, amendments, and plant starts in a garden).
You also need to keep the “weeds” at bay, which in an organic water feature means string algae. Once the aquatic plants get established and start growing aggressively, the algae, like weeds in a healthy garden, will be choked out for the most part. Remember that there will always be green fuzz on the rocks – this is not a pool or spa with sterile water. That green fuzz actually serves as another filter to produce crystal-clear water (we call it the pond patina).
The process of bringing a living water feature to life takes a bit of time and patience. It may take a bit longer, or it may happen quicker, depending on many factors, including the weather. Each water feature is an individual and will balance when it’s darn good and ready. But we promise you that this WILL happen as long as no one tries to “help” things along adding chemical treatments and "quick fixes." Once you add chemicals to your pond, it perpetuates that process and becomes a chemically-dependent water feature.
Pond Ecosystem in a Nutshell
Here are the key ingredients to a healthy, natural-looking ecosystem pond that remains low-maintenance:
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WHAT IS ALGAE?
Algae (Life Sciences & Allied Applications / Biology): unicellular or multi-cellular organisms formerly classified as plants, occurring in fresh or salt water or moist ground, that have chlorophyll and other pigments but lack true stems, roots, and leaves. Algae, which are now regarded as protoctists, include the seaweeds, diatoms, and spirogyra. [from Latin, plural of alga seaweed, of uncertain origin].
What can I do about the algae in my Phoenix Pond?
Well, okay, but not everybody is excited about its presence in their backyard pond, right? If you have a living pond, with plants and fish, algae is going to insist on being a part of your ecosystem, especially in the “winter” months here in Phoenix when the other plants are dormant. The fact of the matter is, when the growth rate of algae is controlled, algae is a beneficial part of your ecosystem and helps maintain healthy water quality through several functions:
In all seriousness, we know it can grow out of control and make our ponds and streams unsightly. Once it starts growing beyond just fuzzy rocks (we call it pond patina) and becomes more of a filamentatious algae that exceeds a couple of inches in length, many people prefer to take action to stop its growth. Of course, once your plants start growing aggressively, they’ll take a lot of the nutrients in the water and effectively starve out the algae into submission.
However, there are a couple of more aggressive methods of ridding yourself of this aquatic weed. The cheapest method is to simply hand-weed it out and use it. That’s right, it has uses: you can compost it or even use it directly as a natural mulch around plants such as roses. It’s very nutrient-rich. If you don’t want to hand-weed it, you can use a water treatment product to break it up, or starve it out — just make sure you clean your skimmer basket often during this process!
Can I just use an Algaecide in my Phoenix Pond?
PLEASE don’t run out to the pet store or pool supply and buy an algaecide! This chemical will indeed kill the algae, which seems like a good idea at the time, but what happens is that it dies and sinks to the bottom of your pond. Now, what do you suppose happens to dead plant material on the bottom of your pond? It becomes food for more algae and other, less desirable anaerobic processes that fowl your pond water. Once you resort to chemistry to control your algae problem, chemistry will become more of a hobby than the water gardening, and you’ve created a chemically-dependent water feature.
So you must ask yourself….Did I get into this hobby for the love of aquatic plants, amphibians, dragonflies, and fish?……or for the love of practicing water chemistry?
In summary, algae is a fact of life in the world of ponding. It's part of the ecosystem. If this is not something that you wish to deal with, then a non-living system is going to be more to your liking. The more you know...
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Are you considering building a pond? How tough can it really be, right?
If you're going to do it yourself, here are 10 common mistakes that you can avoid with a little preparation. Remember: Proper Preparation Prevents Piss-Poor Performance.
Starting with the design of the pond, Phoenix homeowners too often place their DIY pond in an unused area of the property or in a low spot that collects water. Both of these locations cause problems. Unused areas of the landscape are unused for a reason and it's a waste to put a key focal-point feature in an area that won't be seen regularly. Out of sight, out of mind … meaning nobody will care for it.
Low spots that collect water are challenging to build in (high water table) and water quality can suffer from too much runoff and pollutants entering the pond system. Rainwater harvesting and stormwater management in Phoenix are completely separate conversations from a simple fish pond.
Underestimating the amount of physical work involved with a pond installation is very common. As professional pond contractors, we are regularly asked to complete ponds in Phoenix that are partially excavated by a homeowner. Unless you dig for a living, it's tougher than you think! Proper pond excavation is something that needs to be thought out carefully to provide shelves and pockets for plants. If you just dig a hole and slap some rubber or plastic down, it's technically a pond, but you may not like the ramifications of doing it that way.
Creating Steep Sides
And speaking of excavation, digging a deep bowl with no provisions for shallow areas makes stacking stones on the inside of the pond in Phoenix very difficult. And they won't stay put, either. The stacking would be unstable and since there aren’t shallow areas, it is difficult and dangerous to get in and out of the pond for maintenance. Plus, there's no place or ledges for aquatic plants, the majority of which grow in less than 12" of water, even in Phoenix.
A shallow pond in Phoenix is obviously easier to dig than a deeper one, but if it’s not deep enough, the fish won’t be able to over-winter in the northern part of Arizona. And if you live in the central or southern area, your pond won’t stay cool if it’s too shallow. Fish don’t like hot ponds in Phoenix! 18" is the least amount of finished depth (after the rocks and gravel have been installed) that you want in Phoenix, and that's for goldfish. Koi need a bit more elbow room, and we recommend 24" minimum depth.
Lack of Ledges
A common mistake is when the pond is excavated in a bowl fashion, with gently sloping sides that get deeper towards the middle. This is difficult to disguise with rock since gravel will slide towards the deep area and boulders take up too much room. This will cause an unstable build and is a recipe for disaster and potential injury when maintaining the pond.
Improper Use of Rock and Stone
An installed pond in Phoenix is enhanced with rock to give it a desirable natural-looking appearance; a typical feature will use several tons of stone. That can be a lot of wear and tear on the family minivan, and it needs to be moved and stacked properly for stability.
Many do-it-yourselfers will decide this is too much work and they'll choose small, manageable stones that are easy to move and stack. While the work might be easier, this results in the pond falling short of aesthetics. Also, the pond loses the structural stability provided by the larger, more difficult-to-move boulders. In some cases, the novice pond installer will just eliminate the stonework altogether, which then eliminates the natural-looking feel that was the goal at the onset of the project.
Without rock and gravel, the system fails to function properly because stone not only lends to the aesthetics of the feature, but also functions as a habitat for colonization by a variety of beneficial organisms from bacteria to crustaceans… all critical to the success of a natural-looking, organic ecosystem pond.
Again, a small pond is easier to construct (less digging and rock placement) but it’s actually harder to maintain. A small feature is less stable than a larger volume of water, and most people end up making the water garden larger later down the road because they not only love it but their plants and fish outgrow a small feature. And then you'll need to decide whether to simply live with what you've created with all that blood, sweat, and tears, or to do it all over again.
Lack of Proper Filtration
Consumer thought is that real lakes, rivers, and streams function without pumps and filters, so why does their backyard pond need it? Well, that’s not even a close comparison because it’s completely different hydrology. Do-it-yourselfers sometimes purchase inadequate filters or will purchase components “a la carte.” It may be cheaper to purchase the items piecemeal, but it's challenging because different manufacturers use different fittings, and now you need to "McGuiver" things to work together, versus having everything designed to work as a unit from the get-go. Efficiency and simplicity will create a better system for your pond.
Poor Access/Staging Area
Before you get started, think about where to place your rock and gravel when it’s delivered, or where you want to place the dirt during excavation. Poor planning can lead to having little to no room to get in and out of the property during the construction process, potential tripping hazards, etc.
Improper Berm Size for Waterfalls
If the mound or berm area for the waterfall is too small or too steep, then the waterfall will look out of place and more like a volcano than a waterfall. The berm and waterfall need to be scaled according to the size of the property and the feature. Many people want a big waterfall that looks and sounds great, but it can become difficult and expensive to build, and it can overpower the space you have set aside for your pond.
The waterfall needs to fit with the property and lifestyle of the pond owner -- and, just as important, the pond needs to be large enough to contain the splash generated by the waterfall: splash width is two times the height of the fall.
There are more tricks of the trade, of course, but we don't want to give away ALL of our secrets!
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Did you know that fish possess body language? If you familiarize yourself with the good body language in fish, you’ll be able to also recognize bad fish body language. Then you’ll be able to diagnose and treat your fish before any illness or situation becomes too severe.
Let’s first take a look at good body language in your pond fish:
Some examples of bad fish body language include:
Loss of appetite
When fish lose their appetite, numerous possibilities loom but without any additional symptoms, you could suspect some deterioration in water quality. In particular, warm water with low oxygen adversely affects fish appetites, which you’ll typically see during the hottest summer months. In ponds that are more than four feet deep and without water movement in the deeper areas, the oxygen levels sag, which can result in suffering fish. In either situation, adding an aerator to boost oxygen levels in the pond could be a simple fix.
Fish may also lose their appetite if nitrogen is imbalanced. When the nitrate levels climb in established ponds, fish will lose their appetite. A quick water test will let you know if nitrate is to blame. If nitrate is ruled out, then it could be a parasite problem. You’ll also notice a loss in appetite when the pond water temperature falls below 68 degrees Fahrenheit, which is normal.
When fish hold their fins close to their body, it’s a symptom of illness. Poor water quality and parasites are the likely culprits. Fish with clamped fins look like a fish with only a tail because all the other fins are pulled in close to the body. The fish may just rest on the bottom of the pond with its fins clamped. An assessment of water quality is the place to start. If nothing is found, the fish likely has a parasite that needs to be addressed (see how to identify and treat fish parasites).
Resting on the bottom
A common sign of illness is when the fish rests on the bottom of the pond. The most common cause of this bad fish body language is high water temperatures, high nitrates, and low oxygen levels. Parasites could also be the cause. Test the water, and if nothing is found, you’ve probably got a parasite issue.
Laying on the bottom
This behavior is slightly different because the fish will lay on the bottom of the pond on its side. This is a sign of severe, life-threatening stress. Usually, very cold water is the cause of this bad body language. Water quality and overwhelming parasitism can also cause this.
Stiff swimming with clamped fins
Stiff swimming is a serious sign in fish and almost always points to poor water quality, but the most common cause is parasitism, which is then swinging into a full-blown bacterial infection. Start by testing the water, and if nothing is found, a biopsy can be conducted to confirm the presence of parasites. You can also closely check the gills of your fish for signs of bacterial infection.
Piping at the pond surface
When fish are gasping at the surface of the pond, it’s highly illustrative of two things. Either the pond water doesn’t have enough oxygen in it, or the fish can’t get that oxygen because its gills are being wrecked by something. Adding an aerator typically alleviates this problem but if it doesn’t, you likely have a parasite problem.
Less active or floating in water
Less activity isn’t necessarily a sign of illness, but you’ll want to keep some things in mind. Low oxygen levels can cause the fish to resist higher activity and foraging behaviors. This would be especially true if the listless less active fish are the larger ones whose oxygen demand is higher. Warm water carries less oxygen and if the pond is warm and there’s minimal water turnover from a waterfall or aerator, this could be a contributor. Adding a pond aerator will remedy this problem within four to six hours. If the fish becomes actively engaged again, you’ve solved the problem. If not, suspect the presence of a parasite.
Flashing, or scratching, is bad body language when it’s common among your fish. It’s not uncommon to see a fish flash or scratch on the pond bottom of other submerged ornamentation. This isn’t considered a problem. However, if you see many fish scratching or flashing every hour, that would be bad body language and considered a problem. Flashing can be caused by several things, but your main suspects are the pH level of the pond or a parasite.
Once you become familiar with good and bad body language in your pond fish, you’ll be better equipped to remedy any negative situation and provide them with a healthy, happy home.
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