"This is a film about a man and a fish - This is a film about dramatic relationship between man and fish - The man stands between life and death - The man thinks - The horse thinks - The sheep thinks - The cow thinks - The dog thinks - The fish doesn't think - The fish is mute, expressionless - The fish doesn't think because the fish knows everything - The fish knows everything."

Aquarium – How does it sounds to you? Thanks to knowledge sharing and new technologies in fish keeping, this hobby can be enjoyed right now as never before! By sharing our experience on this blog we would like to contribute to a promotion of this wonderful hobby.

Contrary to a new smartphone, which “wish” to be a status thing, the aquariums actually contributes to its owners lifestyle where it really matters.
Educational reasons: To teach our child to care for something regularly and feel important and responsible for something big. And of course, to learn to bear all the consequences (very unpopular). More generally, to show our kid (and to remind ourselves), that (not only) in that small world of aquariums it is all somehow binded together (i.e. polluted water = dead fish). And to demonstrate how easy it is to destroy it all by lack of knowledge and ignorance, or simply by losing an interest (often the case). And last but not least, to teach our kid to endure and deal with many smaller or bigger setbacks.

Therapeutic reasons: Surely you have already heard about relaxation techniques that require the "patient" to visualize some peaceful green scenery. Now, due to our aquarium, we have such "live" scene constantly in sight ... Fish keeping is also a (very) "slow" hobby, which is in a fast paced world on its own anti-trend way incredibly relaxing. On the other hand, in our opinion, it is not true that the aquarium hobby is not adrenaline hobby - just wait for the first Gourami territorial fish-war, or the first spawning dance of the Cardinal Tetras or childbirth of a Guppy. Such an experience you will not forget so easily (in a good sense). We are also not aware of any allergic reaction to aquariums! And yes, the aquarium is also a nice piece of furniture.

It took us two days to set up our 130 liters sweetwater aquarium. The aquarium is a SERA Biotop LED Cube 130 XXL. It stands on a Sera Aquarium Cabinet. Aquarium size and a stand-alone concept was fitting our needs and possibilities the best.

There are many good publications about setting up the aquariums, just to name a few, we can recommend for a start the free Sera leaflets, available here, or a free Slovak/Czech magazine E-akvarium.cz, available here.

AQUAEL Moonlight LED is used to light our aquarium during the nights. Day lighting is original from SERA aquarium set. There are two fans used to cool it down which are the noisest feature of our aquarium.

SERA CO2-Start tabs were firstly used to quickly enrich the water with a CO2. Later we introduced also a Dennerle CO2 BIO 120. Water inside aquarium and all subsequent water changes are a mixture comming from a Dennerle Compact 130 reverse osmosis and a tap-water in 5 to 1 ratio. Note that the exact ratio for your needs depends on the requirements of your fish and the water parameters in your region. Differences in our water parameters are shown in the last pictured Tetra 6 in 1 Test Strips Kit.

As can be seen in its original manual, SERA offers for a MARINE version of its aquariums an UV-C lamp feature. To get similar UV-C filtration in our sweet-water aquarium a further modification was required. First we bought an UV-C SERA spare part lamp which unfortunately due to its poor packing came broken. Our second order of the same UV-C lamp and a UV-C starter was packed better. A power source was also bought separatly. Installation was then essentially simple, only a pump hose needed to be shorten for a length of the UV-C lamp body. Whole system with a pump runs constantly 24/7. The UV-C lamp is very beneficial, in our opinion, to increase an effect of filtration and help to limit the fish diseases without any need for extra chemicals (medication).

To further increase an effect of the water filtration without a need for chemicals and to prevent the fish diseases in such limited environment which aquarium represents, we are also using Philips Tropical Aquarium Purifier. Originally we installed its ozone mixer output (called Venturi in an installation manual and made by EHEIM) on main aquarium pump output (behind the UV-C lamp). Hoverer the SERA pump turned to be too strong causing substantial water movement in the aquarium due to a jet effect from “Venturi”. Therefore we installed smaller EHEIM pump dedicated only for “ozonizator” allowing us to adjust the whole system as per our needs (quiet operation, minimal current).

The ultimate challenge for a fish keeping hobbyist is a success in breading the next generation of his fish. The very first fish we managed to bread were Betta splendens (Siamese Fighting Fish, Bojovnica pestrá), which happened without our intention in the common fish tank without any extra measures. Two white fish survived harsh environment of a fish eat fish world (which probably means that Bettas are real fighters). And also a nice proof that our aquarium is already well established and healthy. The next fish we intentionally breaded in a separate 10 litres breading tank were Trichogaster chuna (Honey Gourami, Gurama medová).

As a special small side project we also breed genetically modified (no wings) laboratory flies which grow to become live food. One can do that even in home for some periods of time. Initially we bought commercially available Drosophila from Hornbach shop, which we are now successfully breeding for our fish. Very interesting article with details about how to do that can be found here. Another small side project for a “home” sourced live food for fry is a salt-water Brine Shrimp (Artemia) which is already quite well known in the hobby. We are currently also experimenting with Daphnia breeding.

While their name and appearance suggest innocence, Angelfish are apt ambush predators and prey on smaller fish (our Cardinal Tetras can tell stories...). Long fins and triangular body shape made these fish an icon in a fish keeping hobby. Interestingly, they also form monogamous pairs and parents do care for their eggs and even fry. A selective breeding of many decades in captivity resulted in several genetic traits. Our are Marble and Platinum Angelfish.

This small and very nice fish is the most numerous inhabitant of our aquarium as we constantly keep at least 10 of them. Despite (or due to) living in black-water, the fishes beautiful blue stripe demonstrates an optical phenomenon of the iridescence colour effect - it appears to change shade of blue (from very light to indigo). Partly due to the high photosensitivity of the eggs which will die if exposed to bright light, it was not breeding in captivity until recently. The female has fuller look, which usually indicates the presence of eggs. If the conditions in aquarium are right, in the middle of the night, she will let the male to swim alongside her, and together, the pair will mate in a series of turns and spirals repeated in several strikes from the bottom to the water level. Clearly Cardinal Tetra is another species that enjoy dancing. Surprisingly it becomes known to the world only after WW2 when found in Brazil in 1953.

We care for the Natural, Flame Red, Powder Blue and Cobalt Blue forms of the Dwarf Gouramies in our common fish tank. These fish are interesting for their famous labyrinth organ, two sensor fins and ability to build a bubble nests. Their mating “dance” is also worth seeing as is a care for the eggs by a male.

Fish actually have wider range of receptors than humans. Ancient Greek sceptics would be surprised how many “truths” can our senses actually reveal to us, well - to fish. Fish have a sort of the sixth sense in form of a lateral line sensing gentle electric currents and electro-vibrations to detect information about the world around them (including their very fish keeper himself). It is perhaps safe to conclude, that our aquarium fish know at first sight more about me or you then we actually do ourselves, as we do not sense electric currents of our bodies. “The fish knows everything...”.
Beside a colour vision that is at least as good as a humans' (though unlike human eye, most fish adjust focus by moving the lens closer or further from the retina), fish also have chemoreceptors responsible for extraordinary senses of taste and smell. Believe or not, they also have ears (with “otoliths” sensitive to gravity and linear acceleration).
In our aquarium, we care for relatively small fish which make human-hear-able sounds - Schallers Croaking Gouramis. Luckily it does not happen too often and is not so annoying/relaxing as e.g. cricket's cri-cri-cri sound is, but is quite similar. Enjoy this excellent Jörg Vierke video for evidence. They do this by rubbing together two parts of their body, so called “stridulation”.

We use 4 different types of fish food (live, frozen, dry and fresh vegetables). Many hobbyists consider the wild caught live food as the best. However, not everyone knows where and how to get a wild food for the fish or find time for such “hunting”. Therefore we consider as best option a frozen food (this one currently) from local pet store. Though, one must be very careful to defrost it before serving, as an ice is something not known to the tropical fish and it can harm or even kill them. So what we do is we remove the appropriate amount of the frozen food from a freezer first thing in the morning, then make us a breakfast (of our food), and just then feed the already defrosted food to our fish… while we are drinking our morning coffee and watching their feeding frenzy. If we are in a hurry, we put it into a hot water to speed up defrosting.

Second common mistake with the frozen food known to us is to re-frost it once it was defrosted (in an accident or after longer transport). There is very high probability that it will rot, obviously, it is then better to throw it away and plan better next time.

Every other week (if we remember) we also enrich the frozen food (while it is defrosting) with few drops of the SERA FISHTAMIN. In the evenings our fish get dry food “out of the box” (in a flakes and tablets form to get it to both, top and bottom dwellers). As a well know feeding rule, we serve to adult fish only what they can consume in 3 minutes (2 times per day, morning frozen, evening dry). Note that there are other rules for a fry feeding.

Occasionally we also provide 1-2 slices of a fresh cucumber or a red/yellow paprika. Especially our Gouramies seems to like fresh cucumbers. After 2-3 days we remove what remained (if snails didn’t finish it already).

Since we are often “out of the office” for a couple of days, we also use a JUWEL automatic feeder which we have integrated into the aquarium lid for ease of use.

Whenever available we also buy a live food (tubifex or mosquito larvas) from local pet stores. However it is said that such food is the most common source of diseases and parasites in home aquariums. Though we had to treat the fish already for illness, we cannot confirm extra bad experience with live food from the pet stores. Since fish really seems to prefer live food and it also seems to help to prepare them for mating, we took that risk so far.

"How I wish, how I wish you were here - We're just two lost souls swimming in a fish bowl, year after year, running over the same old ground - What have we found? - The same old fears - Wish you were here."