The bulk of the maintenance that has been happening on this tank since October has involved topping up the evaporated water, filter cleaning, manually removing algae and water changes.


One of the issues that the family which has the tank had was that topping up the tank with a bucket disturbed the substrate. I generally avoid the problem by balancing the bucket of new water on top of the tank and syphoning it in. This helps avoid spilling water all over the place and the water from the water butts tends to be freezing this time of year so I’m sure the fish appreciate not having a shock of cold water. Their solution is to place a mug in the tank and pour the water over that (similar to the plate suggestion that seems to be popular in books).

In the mean time, the die back from the plants kept clogging the filter, which they started cleaning in old tank water, but then replaced the filter media altogether. Luckily this was before the fish were added, but I have reiterated the importance of not replacing the filter media in one go.

Fish - 3

The algae that was removed in the previous maintenance session has not come back after the lighting was reduced and the Spirodela spp. was introduced. They haven’t used the EasyCarbo, but I have now advised a dose of 0.25 ml per day to encourage plant growth as nitrates were high in the test results:

  • ammonia: 0 ppm
  • nitrite: 0 ppm
  • nitrate 50-80 ppm

The predominance of tap water top ups (we live in a hard water area) has caused the water in the tank to be quite hard, but this is likely to be beneficial to the plants in the long terms. At last water change yesterday, we removed 5 litres of water and added 20 litres.

I have trimmed the Limnophila sessiliflora a few times and removed over twice as much Spirodela spp. as I had originally added to the tank. The Cryptocoryne wendtii ‘Tropica’ has shown good growth as well, although Crypt. sp. ‘Green Crisped Leaf’ has remained the same size but now has submersed leaf growth. I added four sera Floronette A root tabs, one under each of the Crypt. spp. and two spaced equally under the other plants.

We also got a dark-blue on the bottom to blue on the top background for the tank and replaced the perspex lid with a glass one which is available for a shocking £20 from Arcadia. It works very well, but really should have come with the aquarium from the start. The glass lid is satisfyingly solid and easier to clean with vinegar than the perspex one.

Hitting the first problems and finiding solutions

By mid-November, the newly set up, fish-free tank already showed some problems, the biggest being the appearance of fluffy clouds of dark green algae along the surface of the substrate. To counteract this, I suggested reducing the lighting period (which had been set to around 12 hours by the family) to 10 hours. I also gave them some Spirodela spp. which is a type of giant duckweed that can have a nice red tinge and a bottle of EasyCarbo, a liquid carbon fertiliser which also acts as an algaecide. We then manually removed as much algae as possible while doing a water change and left it at that. I also gave them some sera Florenette A root tabs (which are best value for money), two of which were inserted into the substrate at the time.

In that 6 or so weeks, some of the plants settled in nicely and some died off. Mainly, the Limnophila sessiliflora tried to take over the tank, while the Bacopa lanigera, Lindernia rotundifolia and Lysimachia nummularia ‘Aurea’ died back heavily. This corresponds with my experience that without investigation and special attention, some plants just take to some tanks while some just don’t.


The other problem that the family encountered is high levels of evaporation as can be seen in the photo below. With the tank temperature set to 24°C, this was unexpectedly high as I get considerably less evaporation in my “hot” tanks. The problem with topping up is that it increases the water hardness in the tank, and disturbs the substrate, but this was resolved later.

In the mean time, I had failed to find my background for this tank, so it was looking a bit bare without one. The sagging lid was also irritating everyone.