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Keeping Tropical Fish in Outside Ponds for the Summer

Eureka red kept in pond Hey there!  This week I wanted to talk about something a little different than my usual cichlid blog. I wanted to share some tips on how you can develop spectacular color on tropical fish in a way you may have never considered.

A few years ago, we moved into a house that had a small pond in the front yard. It was one of those rigid, preformed round ponds about 15 inches deep with a  50 to 80 gallon capacity. We kept a few goldfish in there the first year. They grew and made it through the winter just fine as we expected.

The following Spring, I got hold of some Astatotilapia aneocolor from Lake Victoria, 2 males 3 females to be exact. I was told by the previous keeper that they were aggressive, so I put them in a 55 gallon. I figured that would be plenty of space, since they were only 2.5 inch fish, and that they would leave each other alone for the time being.

Boy, was I wrong. One of the males showed his dominance within 2 hours of being added to the tank, and no matter what I did he couldn’t be swayed. I moved decorations around, gave him a time out for a week in a net breeder, and  I even put him into an aquarium with four 3 inch Black Belt Cichlids hoping he would be intimidated into submission. He went nuts in that tank, too, and started beating up the Black Belts, so back into the original tank he went. He quickly went back to his old ways, dominating and terrorizing the other male. He finally ripped out male no. 2’s right eye.

The Great Outdoors

I wasn’t sure what I could do for him. Then it occurred to me that I did have another place for him to go. The temps were high enough outside, so why not? I decided to relocate One Eye to the pond outside to give him a chance to recover. I watched to make sure that the other fish (goldfish) didn’t bother him and they didn’t. In fact, by the end of the week ol’ One Eye was the sole proprietor of the pond.

For the next few weeks, he ate well and still came up to the surface to see who was around the pond when I went to feed. I only had a little internal filter system on the pond, and soon the water started turning green. Before long I could barely see One Eye to see his condition, but i knew he was still alive and growing, possibly even larger than the bully inside. He was eating well, besides my offerings he ate insects that fell into the pond, and I also noticed he was scraping algae off the sides.

Meanwhile the dominant male in the 55 was attaining his astounding breeding colors. He was red on top half of his body and yellow on the bottom half with black fins.

The nights started to get into the mid 60’s, so it was time to bring in ol’ One Eye. When I netted him out I was shocked to see that he was an inch and a half larger than my dominant male and his colors were unbelievable! He had a deep maroon upper half and the bottom half was gold…I kid you not. I mean it was so vibrant that I couldn’t help but wonder what would happen to other fish from my collection if they had the same conditions. The following Spring, I upgraded the filter setup to an internal mag drive pump pushing into a Fluval 403 canister filter with the return line feeding a waterfall. I started keeping Albino Eureka Red Peacocks outside in that pond after the upgrade. You can see the results in my photo (top photo, sorry it’s a little blurry).

There is no match for the magic of natural sunlight and the varied diet tropicals can get outside. A friend of mine kept Red Terrors outside, where they bred for him through the season. Summer vacation outside isn’t just for cichlids, it can also be done with platies, swordtails, guppies and pretty much anything tropical if you have a place for them. Even small patio ponds could be populated with livebearers or tetras. Imagine a school of Cardinal Tetras soaking up those sun rays! Any pond will do as long as it doesn’t get too hot or too cold, and as long the fish have a little cover to protect them from would be predators like herons.

It’s a Jungle Out There

While the benefits are great, there are also some cautions to consider. This time I’d like to talk about some of the dangers and pests that may wreak havoc on our poor little fishies.

I was lucky not to have my pond visited by pests, but local stray cats, opossums, raccoons, snakes or predatory birds that may decide to visit your pond at any time.  Even bugs like dragonfly nymphs can prey on young and small fish. Ample water movement and surface ripples are usually enough to deter them, but more effort may be needed to deter larger predators. There are some easy ways that you can help to protect your fish while they enjoy their outdoor summer vacation. Personally, I would recommend the live plants. You can use floating foliage like water lilies, duck weed or hyacinths for cover and protection for your fish. Young fish will also hide in the roots and feed on the small bugs that live in the roots. Another solution is the use of pond netting. The netting can prevent many predators from snatching your fish out of the water. Not very aesthetic, but effective.

Pesticides and other contaminants may pose a hazard in an outdoor environment. Toxins can be washed into a pond during heavy downpours or may be blown into the Green Heronwater.  The rish is small as long as you stay aware when applying such products…something to keep in mind. Even the rain itself can be a danger to your fish. Acidic rain can drive your ph to low levels if you have a low kh. Depending on the species you’re keeping, such fluctuations can wipe fish out quickly.  I was able to keep the kh high and the ph stable with weekly buffered water changes so thi swas never a problem in my experiences.

Closing Time

Cool temps are the other concern. It’s important to know when to bring them in. For me, when night temperatures start dipping below 75 F, I know it’s time to bring them back to the tank. You may notice the fish becoming lethargic, and some may even die if you don’t pay close attention at the end of summer. I recommend acclimating them slowly back to indoor temperatures. If the filter running the pond is a canister filter, I would recommend keeping it running on the main tank. Clean it out before bringing it inside, but you’ll be supplying an established filter/biological for your indoor tank, and you don’t have to wait for the whole cycling process. We drain the pond each year and look for babies. You can then either store it till the following year or couple of set it back up in the house for the winter.

I hope this inspires someone else to try some tropicals outside. You wont regret it. Let me know if you have any questions, I’ll be happy to help you out.

Until next time,


The Freshwater African Butterfly Fish – Care, Breeding, Behavior

 In habits, appearance, and evolutionary history, the African Butterfly Fish, Pantodon buchholzi, is one of the most unusual of all aquarium species.  Yet despite having been in the trade for over 100 years, this “freshwater flying fish” (a misnomer, see below) gets little attention.  Captive breeding is challenging but possible, and its fantastic hunting behaviors are thrilling to observe.  I helped to set up an African Butterfly Fish exhibit at the Bronx Zoo, and was not at all surprised when it became a great favorite.  Most of the visitors I spoke with were astonished to learn that such an “exotic” creature, worthy of a large zoo exhibit, was available at many pet stores! 


The yellowish-green to silvery-tan body is marked with an intricate pattern of speckles and lines.  The huge pectoral fins, reminiscent of those of marine flying fishes, lend an uncanny resemblance to a dead, floating leaf when viewed from above.  Long rays extending from the tail and the pelvic fin add to its remarkable camouflage.

FW Butterfly Fish

Uploaded to Wikipedia Commons by Toniher

The African Butterfly Fish’s mouth is noticeably upturned, an adaptation for feeding on insects at and above the water’s surface.  Less noticeable is the mouth’s large size and the many teeth it bears; although it tops out at 5 ½ inches, this specialized predator can take quite sizable insects and fishes.

Utilizing its wing-like pectoral fins and unique musculature, the African Butterfly Fish can explode from the water’s surface to snatch low-flying dragonflies, moths and other insects, and to escape predators.  It does not, as far as we know, glide above the water as do marine Flying Fishes (please see photo). Read More »

Choosing the Right Substrate for Your Aquarium

OnyxThere are hundreds of ways that you can make your aquarium “your own”, from the decor or theme you choose to the plants and fish you keep, and even how you choose to accent your habitat with lighting. You may spend a lot of time anguishing on these aspects, hoping to match the vision you build in your head. One aspect that you may not guve the consideration it deserves is the substrate you choose, but the right gravel can make or break the look of your aquarium. This stuff is more than just rocks and sand, it may be the one thing that completes your perfect aesthetic. Let’s look at some of the popular substrate options on the market and explore why one may suit your aquarium better than others.

Freshwater Substrates

If you have a freshwater aquarium, you have a huge selection of substrate colors and types to choose from. First you have to decide if you’re going for a natural look or for something more thematic or colorful. You can purchase colored pebbles or glass accent stones in every color of the rainbow, but some colors are so vibrant they can take the attention away from the stars of the display, your fish.  Colored stones have their place, and can make for a realy fun set-up, but be sure you know what you’re getting into before you purchase a bulk of neon pink or blue substrate. Often these substrates are best as accent colors mixed with natural selections, or for use in smaller tanks.

The natural look tends to be more desirable amongst most hobbyists, shades of grey, tan and brown. These pebbles mimic the textures of creak beds, river shallows, and other natural habitats where these fish come from, making them feel like their back at home. While not all that eye-catching in a bag, these substrates complement the natural colors of live fish and plants, really allowing them to shine. These selections aren’t monotonous either. There are lots to choose from, different sizes, multi-tone, tumbled or rough, that can be mixed or matched to create a custom blend for your tank.  Keep in mind that the size of the gravel you choose may have some impact on fish and plants. Bottom dwelling or bottom feeding fish, and those who breed and nest in the substrate will generally prefer sand or very small pebbles that are easier to move and shuffle, and softer on fins, skin and scales. Likewise, plants may not root well in pebbles that are too large or rough. You may choose to create varying areas in the tank between larger pebbles and finer substrate like inert sand to accommodate several types of fish and plants.  Inert types of freshwater sands are available, but be sure to choose the right kind, otherwise your water chemistry could be effected.

Specialty Substrates

OnyxThere are also special substrates you can use in your freshwater tanks that not only look natural but also provide benefits to your livestock. These include packaged live sand, flourite/laterite plant substrates, soils and cichlid substrates. Live sand is harvested from a natural wet environment and is packaged with live bacteria intact. These bacteria jump start the cycling process and help to establish marine tanks fast. Plant substrates are naturally colored and sized just right for root establishment. These materials also contribute nutrients to enhance plant growth and vigor. Several substrates on the market are designed to cater specifically to the chemistry and habitat need of Rift Lake Cichlids. These help to maintain pH and hardness, and mimic the rocky appearance of their natural habitats. Some hobbyists also go to the next level for Asian and Amazonian species by creating a soft soil/sand bed using peat, laterite or coco fiber. The natural feel and tannin production helps to make these light-shy fish more comfortable and can make their colors super vibrant.

Marine Substrates

Marine substrates include shell, crushed coral, aragonite sand and similar materials principally composed of calcium carbonate. These substrates will help to increase and maintain pH and hardness. These materials are suitable for all marine set-ups and for Rift Lake cichlids that enjoy similar water chemistry minus the salt. These substrates present little variation from afar, with mostly cream or white coloration with flecks of pink, orange and other naturally occurring shell coloration. There are a few selections that occur naturally in gold or black hues which may be mixed with lighter varieties or used as primary substrate. Incorporating these darker colors may help to keep the colors of your fish more vibrant, as the bright bottom may cause the colors of the fish to appear washed out.

Going Without

Australian GoldIn some instances you may even choose to go bare in the aquarium. Bare bottom is usually reserved for med tanks or quarantine systems, but many aquarists opt for no gravel to make maintenance and feeding easier. While this type of set-up has advantages, there are several things to consider before going bare. Some fish may stress easily or not be able to behave naturally if there is no substrate to cover the bottom glass. This method is obviously not a good choice if you want to house gobies or other bottom dwelling or burrowing species. Rooted live plants will not have a place to anchor without a deep gravel bed, so you’ll also be limited to either artificial plants that suck to the bottom or bunch plants that do not need to be anchored in gravel. Substrate also provides a large bed for nitrifying bacteria…be sure to have ample biological filtration, porous rock, or other media to offer the bacteria a place to thrive.

What it all boils down to is taste. The gravel you choose will complete your aquarium’s look and can play a big role in how your fish behave in the tank. Consider the needs of your fish before you make the final decision on how to “carpet” your tank.

Spawning Fish and Fish Eggs in the Aquarium – A Guide for Beginners

Bettas Spawning under bubble nestWhat could be more exciting for an aquarist than seeing a pair of fish spawn or finding a mass of eggs in the tank? Many beginner aquarists may not realize that their fish have formed a pair, what the fish are doing if they show a courtship ritual or that they are preparing an area to lay thier eggs. When eggs or babies appear, someone new the game may have lots of questions and concerns about what (if anything) they need to do for a successful hatch or to raise the fry.

Chances are you’re doing something right if you have a pair of fish that are prepared to spawn in the tank. Typically conditions must be favorable (clean water, ideal spawning chemistry, ect.) for the fish to be interested in breeding to begin with. If you’ve reached this point you’ll want to know what happens next. Read More »

Cichlid Territories and Aggression

Black DevilThis time around I want to talk about something I hold dear to my heart…aggressive cichlids. Most cichlids have a mean streak towards other fish in the tank, but its a whole different story when that aggression is turned on an unsuspecting aquarist.

Most of the species that exhibit this type of behavior tend to be in the South and Central American cichlid group. The African Rift Lake cichlids normally keep the aggression focused on other fish in the tank, though I’ve had some shell-dwellers who would attack my arms and on occasion rip out some arm hair…truly they can be like feisty little bulldogs. Some larger West Africans and cichlids from Madagascar have also shown brazen territoriality towards me in my many years of keeping them. Read More »