Alexander Foreman's page

Southern Purple Spotted Gudgeon Mogurnda Adspersa


Small and compact with purple multicoloured spots along it's body. Quite nice.


7 - 12 cm.


Unfortunately and unforgivably this fish is extinct in the South Australian gulf division.


This fish has colourful markings that look good under suitable lighting. It is not particularly active in the aquarium but it is easily observed. Will often swim up to people who approach the aquarium, expecting to be fed. Can be trained to take food from the hand. Due to the conservation problems related to this fish in South Australia, I feel very privileged to keep and breed a population of Southern Purple Spotted Gudgeons.


Sometimes available through aquarium retailers. Also obtainable from the South Australian Native Fish Association for members.



Grows to a suitable size.

Happy in a small aquarium (60 cm or more).

Can be territorial bur rarely will harass other fish.

May squabble with its own kind but will not harm each other.

Not particularly sensitive to harassment.

Not sensitive to water quality.

Able to tolerate cold and tropical water temperatures.

Does not disturb plants.


Will eat other fish that are smaller.

Can be tricky to feed only because tank mates may steal its food.

Only eats meat and fish.



Minimum aquarium size: 60 cm long X 30 cm wide.
Water temperature: Tolerates both warm and cold water well.
Water salinity: Freshwater only.
Filtration & oxygenation: Water needs to be kept reasonably clean and always well oxygenated.
Lighting: Not critical, but the gudgeon really looks good under proper lighting.
Plants: Plant are appreciated but not critical.
Furnishings: Dark hiding locations important.



Gudgeon eating beef heart


Southern Purple Spotted Gudgeons settle into the aquarium easily. I have difficulty observing them behaving normally because every time a captive gudgeon sees a human it anticipates being fed and gets all excited. They are poor swimmers and reside on the bottom of the tank when they are not excited. These particular gudgeons seem to be very extroverted, and are not shy. They rarely fight with each other.


I have only been able to feed live and frozen foods to these fish. They ignore pellets and flake food. They eat pieces of fish, beef heart, blood worm, and anything else meaty. Feeding once a day seems sufficient.


Very easy to care for apart from feeding. Keep them away from substantially smaller fish.


Breeding Account for Southern Purple Spotted Gudgeon


Six week old Southern Purple Spotted Gudgeon. This fish is shorter than the width of my finger nail.


One pair of Gudgeons were placed into a 90 cm X 45 cm aquarium, heated to 25C. The tank was bare of furnishings. The gudgeons spawned when the other inhabitants of the tank were removed (various tropical fish).


I discovered the eggs deposited on the side of the tank, guarded and fanned by the male gudgeon. The female had suffered some superficial damage and was staying well away from the eggs. I assume that the male had attacked her after the spawning to keep her away. She was removed immediately.


The eggs developed over a period of four days. I treated the tank with a light dose of 'quick cure' fungacide to prevent any fungus destroying the eggs. The male continued to guard and fan the eggs and refused to eat when I attempted to feed him. I could see the young fish growing inside the eggs.


On the fourth day the eggs hatched. The fry remained attatched to the glass for a while longer before they became free swimming. I removed as many of the fry as I could using a syphon tube. I placed the captured fry into a 60 cm X 30 cm tank that was bare of any furnishings save a small sponge filter. It had no heater or substrate. I estimated that I transfurred 30 fry. Some were not removed from the spawing tank (they were too good at hiding!). The fry were so small as to require the use of a powerful torch to spot them.


Initially I fed the fry on 'liquid fry food for egglayers', three times daily. I also placed two mystery snails into the tank to eat any left over food and prevent decay. After six weeks the fry had grown a fair bit so I switched their diet to frozen bloodworm. I seem to have around 30 fish.

Tiny Southern Purple Spotted Gudgeon fry, swimming about in their nursery aquarium.


'Doug' the sleepy cod. These fish are cute when they are small, but they grow to a large size and love to eat other fish.



The first thing to do when starting out in fish keeping is to do your homework. Borrow as many books on aquariums as you can find in your local library. The Adelaide Lending Library has a few good aquarium books. Some books neglect certain aspects on aquarium maintenance so make sure you read at least three books. Books can also be purchased in book stores or aquarium shops. Work out what you want and how to set it up before you go to the pet shop or you will probably end up with something you don't want or can't use.

Decide what fish you want to keep by reading about their characteristics and observing them in the shop. Pay particular attention to the fish's maximum size, water conditions and temperament. Never believe what the sales assistant in the shop tells you. They usually have no idea what they're talking about. This is especially the case with native fish and uncommon fish. I was once sold a sleepy cod under the understanding that it was suitable for the community tank, which it certainly is not!


Never buy a cute looking fish on impulse. Trust me, it is a mistake! Research the fish first.


Believe it or not, the larger the tank the easier it is to maintain. Large tanks do not need to be cleaned any where near as often as small tanks, and when they are cleaned they only need minimal maintenance. Large tanks are safer for the fish than small tanks. If something goes wrong it happens more slowly. Large tanks make fish feel more comfortable so they are less prone to stress related diseases and they behave in a more natural manner. Fish are less likely to fight as the victim has an escape route. Large tanks can hold lots of fish so you don't have to buy more tanks when you feel the need to expand your collection. The only disadvantage is that large tanks are harder to move. I recommend you start with a tank between 120 cm and 180 cm. You should never set up a tank smaller than 60 cm long unless you are very sure of what you are doing.


You can not over filtrate, but you can under filtrate. Air operated filters are not good enough for most aquariums. I recommend the internal power filter. Try to have the entire volume of the tank passing through the filter three times an hour (i.e. if you have a 100 liter aquarium your filter should cycle 300 liters and hour). In my 380 liter aquarium I have one 1000 liter per hour filter and another filter that does 300 liters per hour. That tank has almost crystal clear water all the time.

Avoid placing unnatural objects into your aquarium. Bright colours and sharp edges will do nothing to help your fish. Bright colours will also detract from the appearance of the fish themselves. Use river washed stones and drift wood for decoration. Don't go overboard with aquarium decoration. Provide enough wood and rock work to provide hiding places for the fish but do not clutter the aquarium, make sure that the fish have swimming room.
Buy the recommended equipment and set the tank up as outlined in the aquarium books. Don't introduce the fish too soon.


There are aquarium and fish clubs around the place. The help you can get from the other members of such a club can be invaluable. Some such clubs are listed on the links page.

Making your aquarium look good


There is no point in having the worlds best looking fish tank if it is hidden in a back room is there? Try and place the aquarium in a location where is will both be seen and where the fish will see people. If the fish see people regularly they will not panic or hide when someone comes to look at them.


Having unscratched clean glass makes a huge difference in the appearance of an aquarium. I wash the outside of the glass with diluted methylated spirits and a soft cloth. This inside of the glass I clean with a soft scouring pad and a sponge (no detergent of chemicals). I only clean the front pane of glass and allow algae to grow on the others as fish food.


Super clean glass is fantastic, but useless without crystal clear water. The answer to fantastic water quality is good filtration, water changes and not feeding too much. I find it almost impossible to keep a fully stocked tank clean, so try to limit the density of fish. The filters should cycle the entire water volume of the tank at least three times an hour. Direct sunlight can cause algae to grow in the water, turning it green. Avoid placing a tank where it gets direct sunlight.


Good bright overhead fluorescent lighting is indispensable when you want to show your tank. Try to place the light forward over the tank to show your fish to best advantage. There are different types of lighting available. Try not to use conventional fluorescent tubes, the colour is terrible!


Try and have a background for your aquarium. You can paint the rear pain, attach a printed background or hang a curtain behind the tank. Try hand have the background fairly dark, it adds depth to the tank.


The substrate should be dark but natural. Light coloured substrates reflect light and make the fish look washed out.

The substrate should also be kept clean and free from excess waste. A gravel siphon is the best way of keeping the substrate clean.


Plants look really good, but can be difficult to obtain. I only use the most hardy of plants. Try to keep the plants away from the filter outlet as the current can damage them. Plants need to be illuminated for most of the day to grow.


Use rocks that don't have sharp edges and drift wood to complete the look of your tank. Use your imagination to make an attractive setting. Try to keep it fairly simple and don't clutter the tank.

The Oscar is an aggressive fish. It can give any fish a hard time. Be sure to only keep it with other fish that can protect themselves.

Oscars also have a bad habit of digging up plants and rearranging tank furnishings. Only simple and rugged items like heavy rocks and large stumps will do for a tank housing an Oscar.


Food tips


I keep a lot of predatory fish and they can prove to be a handful. The first thing it to try and avoid buying prepared foods from aquarium retailers due to the high priced that they charge. I feed about a kilogram of food to my predators each fortnight so there is no way I could ever afford to feed them using such foods.

The first and probably best type of food that I use is white bait and other bait fish. I get my fish from bait shops. If you do this make sure that you are getting good quality fish, many bait fish are rotten and will kill your pets. You can also sometimes buy small fish from seafood shops. I simply defrost the fish and throw them into my tanks whole, unless the fish are too small to eat them whole. In that case I break the fish up, but still throw in everything including the head, stomach and back bone. In my opinion this is an excellent and natural diet. Using marine fish to feed to freshwater fish also ensures that parasites and germs are not introduced.

Another food that I use as a supplement is beef heart that I buy from a butcher's shop. Red meat can be dangerous to fish because they have a hard time digesting fats. I remove all the fat and them mince up the heart. I then freeze portions that will last for three days at a time. All of my fish love beef heart.

Fish are like us in that they should have a variety of foods. I also feed cockroaches, live fish and some prepared foods to my predators to keep them happy.


These fellows are easy. The smaller ones will take flake and the bigger ones will take pellets. I change brands of flake every so often for variety, and throw in something special every so often like some blood worm of beef heart. Vegetarians appreciate lettuce leaves as a snack. Use the dark green leaves as these have the most nutrition.

A Murray Cod makes a rewarding pet, but it needs room to grow. The small fish shown here will eventually become physically larger than most people's fish tanks!


Good practices I learned the hard way


Avoid placing aquariums in the spare room/shed. The fish do not acclimatise to having people around and will be afraid of you. Also you may forget about them every once in a while (which I sometimes did). If you can see the aquarium all the time then you will be more inclined to keep it clean and healthy. A neglected aquarium is the fastest way to losing interest in this hobby. I keep all my aquariums in the lounge room and the bed room.


There is nothing worse than having fish tanks that require constant attention. That is why I use big tanks with good filters and reasonable stocking levels. I can leave my fish tanks virtually uncleaned for up to a month if need be.


Change about one third of the total water in the tank each fortnight (or each week if the tank needs it). You should never have to empty out the tank and give it a more extensive cleaning if the filters are doing their job and you are not over feeding. Failure to water change regularly can lead to disease, stress and even the death of your fish.

A schooling fish will generally feel insecure if kept by itself. It is a good idea to keep such fish in groups. They will behave in a more natural and confident manner. You will benefit from this because the fish will be less reclusive and will have better colour.
Make sure you have at least one empty tank which is set up and ready to go in case you detect a sick fish, or purchase a new one. New fish must always be isolated before being released into the aquarium.

No magic cures, no flashy chemicals. Look after your fish and they will look after themselves. Research you fish so that you understand them. Set up your tank correctly. Don't overstock or under filtrate. Make regular partial water changes, don't cheat and change most of the water every so often (I killed some fish doing that). Don't mix incompatible fish. Feed a variety of food. Quarantine new fish. Do these things and fish disease will rarely have to be prevented.


Turning off most types of filters kills the bacteria that accumulate in them. This bacteria is in fact the stuff that is cleaning your tank. By turning off your filter you are basically rendering it useless. You might as well throw it away.


Young growing fish eat a lot more than older larger fish. When their appetite starts to drop off, make sure you reduce the food input! If you feed your fish red meat, ensure that it is totally fat free. Fish cannot digest animal fat and will eventually die from cholesterol buildup.

I have found that many fish hate members of their own species but will tolerate fish of other species. Unless you are sure that the fish gets along with it's own kind, keep only one of each. This is especially the case with cichlids and many natives. Only schooling fish appreciate company.

This Southern purple spotted gudgeon lived in my lounge room and was no stranger to people. It's mate, however, had been kept in a back room and cowered at the site of a person.