On trying, and failing, to count to 20

“I think that’s 12” he said, from the top step of a wobbly stepladder. “Although they won’t stay still long enough for me to count them properly. I haven’t counted the rest, but there’s no way there’s another 20 in there”.

“That’s ok, we’ll take them all, even if there aren’t going to be as many as we wanted”.


Last Sunday (written last week, so really the Sunday before last), we decided to buy more fish. It’s an idea we’d played with for a while and because we’ve finally finished the light box and changed the water it seemed like a good day to act on it.

We have discus fish. They are generally pretty friendly, but they are liable to eat anything small enough to bite and slow enough to get bitten. On the other hand, they don’t eat all the food they’re given on any given day. The uneaten fish food makes the water ‘bad’ (I have no idea how. I think it has something to do with the pH value, but I don’t actually know), and encourages the wrong sort of plants to grow.

We need something to eat the leftover food, without getting eaten. We don’t want to spend loads of money on them, but we also don’t want something that won’t work in our aquarium.

To make things more complicated, discus fish are originally from South America and DB doesn’t want to mix continents. The choice of South American fish bred to survive in limescale-y German tap water isn’t huge.

The number of fish that fulfill all the criteria AND can be found in fish shops which open on Sundays is even smaller.

We chose Trauermantelsalmler*. They need a herd (or a school) to be happy**. 50 would be ideal, but even the cheaper, not-yet-fully-grown fish are expensive en mass, so we agreed 30 would be ok.


I think it is less than ideal that no one had told the trainee fish salesman that the fish scoops have extra long handles so that they can be hung on the side of the aquarium to save several journeys up and down the wobbly ladder. Especially when it was obvious that he was not a natural ladder climber, wobbly or otherwise.

Considering that we were in the fish department of a D.I.Y. shop, I think it is bad marketing for the trainee fish salesman to have a wobbly ladder at all

It would’ve been nice if he’d left a bit more water in the fish-transport-bag too, but I think he’s at the beginning of his training and will learn the rest soon. He might learn it more quickly if the dragon-like lady-at-the-till tells him she couldn’t lie the bag down because she’d have stranded them in the shallows.


As we left the till ready to crunch our way accross the frozen carpark to the van, I tucked the fishbag inside my jacket. I pulled my T-shirt up, and allowed the warmth to travel from my stomach to the water. The fish need at least 26 degrees (Centigrade, this is Germany ;)), 28 is preferable and 30 is about the upper limit. I am always cold in comparison to DB, so I figured I was unlikely to cook them on the 15 minute journey home. I kept the heated seat turned right up to avoid freezing myself :).


DB opened first the aquarium lid, then the fish bag, as soon as we got in, before we could get waylaid with timewasting activities like taking our shoes off. (I love traipsing snow into the house πŸ™‚ (Really. I just don’t get the chance all that often – DB is such a spoilsport!)).

The process of transferring fish is pretty much the same whatever fish you buy: a bit of aquarium water is added to the bag, which is then resealed and left to swim in the aquarium. This lets the fish get used to the new water, without getting cold.***

Half an hour or so later DB tipped out most of the water in the bag (so we didn’t end up with the shop water in our tank****) and replaced it with ‘our water’. Another few minutes acclimatisation and they were ready to explore.


Theoretically, all new fish should go into a quarantine aquarium to make sure they’re healthy but we don’t have a quarantine aquarium, or even space for a part time quarantine aquarium, so we decided to risk it. Actually, it wasn’t really a decision. It was already clear that if we were going to buy new fish we were going to risk the health of the existing fish. Sometimes you just have to accept the risk and carry on.


As soon as they left the bag, the new fish raced to the end of the tank, and around the perimeter, and back and forth along the front,Β  presumably to find the best means of escape…

Black Tetra in Aquarium
Finally free! (the rest are already out of the picture)

There is none. Poor things. (Although I’m pretty sure they’d favour life in a substandard aquarium over life on the carpet if they ever did escape).

Took them a while to realise though – even longer than it took me to count them and be happy with the result.

There are 22.

The trainee had counted them and reached 20. He’d written 20 on the bag, and we’d paid for 20. I’m not going to complain, but,

“What do they teach them in these schools!”*****



* Black Tetras. Also known as black skirt tetra, petticoat tetra, high-fin black skirt tetra, and black widow tetra. The German literally means “mourning mantel Tetra”

** not many people I know who need a school to be happy πŸ˜‰

*** If you’re just moving them between aquariums, you can use a bucket. There’s usually enough water in a bucket, that it won’t get cold, so it doesn’t need to be floated in the aquarium..

**** helps to reduce risk of disease transfer

***** The Lion the Witch and the Wardrobe – C.S.Lewis


[Edit, 11. Feb: I thought someone would make a clever comment involving catch 22, but no one has…]

On filling an aquarium / Or preparing one – part 2

Usually, when setting up an aquarium (especially for fussy fish like discus), one starts planning a month or so in advance. That leaves plenty of time to fill it up, and let the pump, the filter and the water get used to each other. There’s enough time for the chemicals in the tap water to lose their strength (please don’t ask me how – I have no idea), enough time for the right sort of bacteria to settle in, enough time for a mini eco-system to evolve – or at least for the water to get a green tinge!

We didn’t have that much time.

Instead, we hung the new filter into the old aquarium for a couple of days.

Usually, in an established anquarium, one changes about a quarter of the the water every 2 weeks (minimum). Ish. The water is syphoned out and replaced with fresh (tap) water. Officially the water you put in should have the same temperature as the water you take out but ours seem to like it a little bit colder – they swim in and out of the ‘jet’ like anything!

While we were setting up the new aquarium, we changed the water approximately every 3 days. We didn’t take nearly a third though, more like a sixth. We syphoned the water into the new aquarium instead of into the garden. The old aquarium was topped up and the process was repeated a few days later.

Once the new aquarium was about 3/4 full, we took the new filter out of the old aquarium and gave it a new home in the new aquarium.

We added the air-stones*, some wood for hiding behind, and a good handful of water plants and waited for the last water change.

Once the aquarium was full, and had been run though the filter for another couple of days, we were finally ready to transfer the fish.


Fish aren’t really good for the impatient. Unless they’re learning to be patient…


Even our accelerated set up took a couple of weeks. It was ok, but only just. If you have time for it, I would always recommend letting it settle down a bit more before adding the first fish. I think having ‘ready made’ aquarium water (from the old aquarium) is awesome, as long as you fish are healthy and happy. If they’re ill, and you buy new fish, I think I would rather wait longer and keep the aquariums separate.


Any advice welcome πŸ™‚


*air is pumped through a porous stone ao that bubbles come out, circulating and oxygenating the water.

On preparing an aquarium – part 1

We started with the glass.

The DB’s father had 2 aquariums, neither of which was in use.

The short version would be: we chose one, washed it out and took it home. The real life version was more complicated but that’s not relevant here.. πŸ™‚


We had an aquarium we wanted to use.

DB knows a welder who let himself be sweet talked into welding us a table exactly the right size for the aquarium.
Presumably one can buy ready made aquarium tables, but having one made to fit exactly is a lot cooler. Besides it’s better to have a lip on the table to give more support and most normal tables don’t have them.

We’d bought a tin of metallic blue paint for the garden bench so we used that for the table too.

Next step was getting a piece of wood and a piece of polystyrene to fit snuggly inside the table frame. The wood adds stability and the polystyrene insulates the aquarium (the water temperature is above room temperature, depending on what kind of fish you have).

Once everything was dry/cut to size DB and his dad carried it all into the sitting room and put it together. They put bits of cardboard under the feet to protect the tiles.

The next stage was preparing and filling it.

We bought and washed 2 small sacks of gravel.

Washing gravel involves pouring some of it into a bucket, running water into it and dipping your hands through it to the bottom of the bucket, scraping up the gravel at the bottom and bringing it to the top. Repeat.

It isn’t entirely necessary, but the dust makes the water cloudy and so means more work for the pump later.

I watched DB at the beginning and thought it would hurt my hands, but he said it was therapeutic so I tried it too. He was right, it didn’t hurt, it actually felt more like digging a hole on a gritty beach.

When the water ran clear we tipped the gravel bucket by bucket onto the floor of the aquarium. There doesn’t seem to be a perfect gravel depth, it’s more like guesswork and luck. 2 sacks was more than enough for 50mm of gravel.

On baby fish – part 2

(Late March 2014, additions September 2015)

As the fish grew bigger and bigger, their parents grew more and more tired of being their only source of food/nutritional secrete*.

We read about baby fish online, we asked the staff at fish shops, we phoned a professional fish breeder. We came to the conclusion that it was only a matter of time until we had to step in and do something.

The ‘Something’ involved procuring and setting up a new aquarium, asking a local welder to make us a table strong enough to support an aquarium containing 40 fish and almost 300kg of water and gravel, getting a large piece of wood (cut to size by the man in the wood shop) for the lid, buying aquarium gravel, a water filter, an air pump, a water heater, several metres of thin silicone tubing, a handful of water plants and a tub of antemius* eggs as well as 2 lights, 2 hinges, and a handle.

DB built the lid while his father and I built my new bookshelf πŸ™‚

We* also made ourselves 3 glass antemius breeding bottles with 2 way taps. The aquarium then needed a couple of sheets of glass to stop the water evaporating too much so DB cut some to shape and smoothed off the edges so that even I could slide them without injury.

By the time the aquarium table was painted, the aquarium set up, the water stolen gracefully from the original aquarium by means of a hosepipe siphon, and the first of the antemius eggs starting to hatch, the DB was as exhausted as the fish-parents, though not missing as much skin.

However, there was still something missing….
…..the fish themselves!!


*Discus fish parents produce the fish equivalent of milk. It makes them darker, presumably so they aren’t easily seen by predators, but that’s just a guess. As soon as the babies hatch, they start eating their eggshells. Once they’re gone, they leave the slope they were born on and latch onto a nearby parent. There, the baby fish eat the fish-milk off their parents’ scales. After a while, the babies are so big (and so hungry) they start eating bits of scale too. Being eaten out of house and home (by your offspring) has to be better than being eaten (by your offspring). In the wild, the parents swim away from the monster-babies, until they get the idea that the sea is full of other edible things. In an aquarium, they’re liable to be plucked to death.

**Artemias are mini shrimps. They aren’t exactly the natural food choice for a discus fish, but they will do. Most captive discus fish eat them. They are really very very tiny, but baby fish are very very tinier. There is no way they can eat fully grown Artemia. This means you have to start breeding the Artemia, and feeding the larvae to the baby discus fish. It’s not exactly difficult, but it is fiddly.

On baby fish – part 1

And another one from the draft folder… (late March 2014)


The DB was given an aquarium a few years ago*. He bought 5 different sorts of fish, some lumpy bits of wood and some fish food and has looked after the fish ever since.

Then he met me. He showed me the aquarium and I nodded and said something like, “yes, that is indeed an aquarium, and those are indeed fish”. I couldn’t see the attraction, but hey, each to his own.

As I spent more time at his house, I spent more time looking at the fish. I began to differentiate between them. They were different colours for starters, but they also had different characteristics… No, I wouldn’t’ve believed me either ;).

The fish started noticing each other as fish, and not just colourful obstacles.

In January, I moved in.

The fish, specifically 2 of the discus fish, started laying eggs.

The first few batches – if you can have batches of eggs – were eaten before they could hatch.

The next couple of batches hatched but disappeared while we were painting my flat.

I finally arrived, with all my possessions (although some are in DB’s dad’s cellar), on the 1st of March.

By midday on the 3rd, they’d laid new eggs.

We watched them hatch, left a light on to help their parents look after them. We rejoiced every evening after work when they were still there, exclaiming (loudly) how big they were. It’s astonishing how much a fish can grow in the course of a day.

I was worried that they’d get eaten again, so DB put a wire mesh across the aquarium. It took a couple of attempts, but finally all the ‘wrong’ fish were on one side, leaving the happy fish family on the other.

They’re 3 weeks old now.

It’s amazing how attached you can get to a fish. Or 50.

* like more than 10 years