Buying aquatic plants and tank set-up
You can experience being ripped off when buying plants. For this reason, a little attention is really advisable.
Specialist staff in pet shops who are well versed in aquatic plants are few and far between. It therefore makes sense to look at a few dealers first before spending large sums on aquatic plants. Once you have had a good experience, however, you should remain loyal to this retailer. The cheapest offer is not automatically the cheapest for the same reasons.
When shopping, you should make sure that you know which plants you want and need. You should not let the seller persuade you to buy plants that you do not know.
Plants should look fresh, i.e. have few or no dead parts. You should also not buy plants that are covered in algae.
The cheapest place to get plants is where they are not under water. If this is not possible, choose pet shops with a high throughput of aquatic plants, as the plants will only be in the sales tanks for hours or a few days.
Emersed (above water) plants are also practically algae-free. Almost all of them come from aquatic plant nurseries to pet shops.
The nurseries grow most aquatic plants, which are mainly marsh plants and not "real" aquatic plants, above water (emersed). The emersed plants must first adapt when they are submerged under water (submersed), i.e. placed in the aquarium. Submerged-grown leaves often, but not always, look completely different from emersed-grown leaves from the nursery. One more reason to before buying about the plants you may be purchasing.
The emersed leaves die relatively quickly and new leaves grow that are adapted to underwater life. However, this varies from plant species to plant species. As a rule, stem plants have fewer conversion problems than rhizome plants. Stem plants sometimes continue to grow almost immediately after introduction. Rhizome plants such as echinodors can take a few weeks or even months to fully establish themselves. completely completely acclimatised.
However, you should be able to see the first new leaves sprouting no later than 1 - 1.5 weeks after adding them to the aquarium.
There are also purely aquatic plants that cannot be kept above water, such as Vallisneria. These are also only offered under water by retailers (no, you don't need diving equipment to buy them 
).
So-called "in vitro" plants (young plants grown on culture media from the smallest fragments of plants) are also becoming increasingly common in stationary shops and mail order companies. These are free from pathogens and algae. However, they are often quite small and it is sometimes not easy to adapt them to the conditions in the aquarium. With a little experience, however, they are a good alternative.
At the beginning, i.e. when setting up the aquarium, you should make sure that you introduce lots of fast-growing stem plants. They should make up about 80 % of the total plant population. The aquarium should also be approx. 70 - 80 % planted (i.e. only 20 - 30 % of the floor area should be visible from above).
Lush and rapid plant growth is the best and most natural way to prevent algae from growing. Nevertheless, it can happen during the so-called running-in of the aquarium that a plague of algae develops in the meantime. However, this is nothing unusual and occurs relatively frequently. This initial plague of algae can be safely sat out.
Please do not immediately lose patience and resort to the often highly praised algae remedies. All algaecides are poisons and therefore have more or less strong side effects. They are not only toxic for algae, but also for the plants that you actually wanted to protect, as well as for fish, molluscs and crustaceans (snails, shrimps). Worse still, they create a vicious circle by damaging the plants. The plants do not grow again immediately (if ever) after the treatment has been completed, which immediately leads to the next algae infestation, which brings us back to the starting point of the campaign.
It is not for nothing that algae products for aquariums and ponds are one of the top-selling product groups in the aquarium trade!
The following stem plants are robust and grow the fastest
- Heteranthera zosterifolia
- Hygrophila angustifolia
- Hygrophila corymbosa
- Hygrophila difformis
- Hygrophila polysperma
- Limnophila sessiliflora
- Limnophila heterophila
- Rotala rotundifolia
- Cabomba caroliniana
- Ludwigia repens
- Ludwigia palustris
- Ceratophyllum demersum (hornwort)
- Shinnersia rivularis (Mexican oak leaf)
(this and the following lists do not claim to be exhaustive)
Stem plants are relatively easy to move. You can easily pull them out, cut them back (usually not more than twice, depending on the species) and replant the cut stems (cuttings).
Other plants that are not as easy to transplant as stem plants, as they form extensive roots and are keen to remain in place, but which are nevertheless robust and reasonably fast-growing, are recommended to start with:
- Echinodorus tenellus, there is a small (5 cm) and a longer, reddish variety with very narrow leaves (up to 18 cm)
- Echinodorus quadricostatus (up to 10 cm high)
- Echinodorus bolivianus (very similar to E. quadricostatus)
Be careful with large Echinodorus(E. osiris, E. bleheri etc.)! In well-running aquaria they can actually reach or exceed the dimensions given in the literature. A single one of these plants can completely take over a 60-litre or even a 100-litre aquarium.
Not as fast-growing, but robust and not too many of them are also recommended for beginners
- Microsorum pteropus (Java fern)
- Vallisneria spiralis
- Vallisneria americana
The following plants are not recommended when setting up a new aquarium, as they are either too demanding and/or grow too slowly
- All Cryptocorynes (demanding and slow-growing)
- All anubias (slow-growing)
- All Althernanteras (demanding and slow-growing)
- Didiplis diandra (demanding and slow-growing)
- Lobelia cardinalis (slow-growing)
- Rotala macranda (demanding and slow-growing)
- Limnophila aquatica
- ...
There is no reason why you shouldn't buy a pot or two of these plants to bring a little more variety into the aquarium or to experiment a little. It may well turn out that one or other of these species grows well in your aquarium right from the start. However, you cannot expect these plants to prevent algae.
Later, when everything is running reasonably smoothly (approx. 0.5 years), you can replace some stem plants or plant areas in the aquarium with slower-growing or more sensitive plants.
Non-stem plants, i.e. plants with rhizomes, tolerate changes of location poorly, with a few exceptions. You should therefore think carefully beforehand about where to place these types of plants in the aquarium.
A few more tips
- Stem plants do not have to be "pulled" out of the pot, just cut them off and plant them.
- Be careful not to crush the stems.
- Otherwise, the rockwool must be removed from the roots as far as possible, as it can damage the gills and intestines of the fish. However, the rhizome should not be damaged if possible.
- It is better to leave the last bit of rockwool on than to damage the plant. The welfare of the plant has priority here.
- The rockwool often contains a lot of fertiliser. The pots are surrounded by a fertiliser solution in the nursery. Rinse well with lukewarm water.
- The roots should be shortened to a length of 2 - 3 cm with sharp scissors or a knife before planting. These usually only serve as an initial support and will soon rot anyway. The plant will soon sprout new roots.
- Remove muddy brown roots and leaves before planting.
- If the roots are predominantly muddy, you should ask for a replacement in the shop. You can't see the condition of the plant in the pot before you buy it.
- Stem plants should not be cut back too often. Some species do not tolerate pruning well at all, but others become a beautiful bush as a result. Gather your own experience here.
- At the latest when the part of the plant remaining in the substrate becomes unsightly, the plant should be replanted. To do this, cut off the upper part (at least 10 cm or 3 - 4 leaf nodes long) and replant (stake). Pull out the old part slowly without digging through the substrate too much, shaking it a little if necessary.
- Please stick all stems individually, not in bundles or even tied together with lead tape or rubber. Depending on the species, make sure there is enough space between the individual stems. Many species do not like it if they shade each other too much and will quickly shed a lot of leaves.
- Most stem plants are gregarious! They grow better if they are planted in groups of at least 4 - 6. Individual stems almost always take care of themselves!
- If you want to propagate a stem plant more quickly, cut a longer stem into several parts.
A little experimentation will quickly give you experience. - Many stem plants that are allowed to grow along the surface of the water ("flooding") branch out well and become particularly vigorous (e.g. Rotala, Limnophila, Cabomba, Ludwigia). However, they should not be flooded too much, as they then take too much light away from other plants and themselves. Some species also tend to revert to an emersed growth form when flooded (adaptation to falling water levels in nature). They would first have to be acclimatised to submerged culture.
- Aquatic plants need to be fertilised, preferably with CO2.
- Regular and sufficient water changes remove excess nutrients and fertilisation replenishes the depleted nutrients. The more frequently you change the water, the closer you stay to the optimum fertilisation level. This supports the higher aquatic plants in their growth and thus pushes back algae.
We recommend at least 25 - 30 % per week.
The original version of this text was written by Markus Löhner in d.r.t.a.
In-depth reading material on the subject
Aquarium plants / Christel Kasselmann
Plants in the aquarium / Maike Wilstermann-Hildebrand