Understanding Hard Water and Its Impact on Aquarium Plants
Aquariums are lively and colourful features one can access in virtually any space. Whether you’re an enthusiast or a mere occasional observer, there is no doubt that aquarium plants will spice up your tank with their lively features. There are various features to consider when maintaining an aquarium; one of which is known as water hardness. While hard water is a feature seen in most aquariums, its long-lasting effects and the consequences on aquarium plants are peculiar. The relationship between hard water and aquarium plants will be detailed in this article. In this essay, the explanations surrounding the effects of hard water on aquarium plants and the challenges involved will be discussed, alongside to make in order to
What is Hard Water?
Water hardness is the level of mineral dissolution (calcium, Ca, and magnesium, Mg) in water. Water can become hard by moving through soil and rock, causing the slow dissolution of these minerals and increasing depth of water hardness. The concentration of dissolved salts in water is typically measured in degrees of hardness, sometimes also expressed in parts per million, ppm (parts per million) or degrees of general hardness dGH (degrees of general hardness). Soft water has fewer dissolved minerals and is less hard, whereas hard water is more highly concentrated with mineral salts.
Hard water can be categorized into three levels:
Soft Water: 0-60 ppm or 0-4 dGH
Moderately Hard Water: 61-120 ppm or 4-8 dGH
Hard Water: 121-180 ppm or 8-12 dGH
Very Hard Water: Over 180 ppm or over 12 dGH
Such aquariums are a bit more challenging to maintain – especially in growing plants. But the more we learn about these challenges and overcome them, the more likely we are to find success, leading to a beautiful and thriving aquatic garden.
The Effects of Hard Water on Aquarium Plants
1. Nutrient Absorption
Apart from that, hard water can impair the way in which plants absorb nutrients. Calcium and magnesium can compete with nutrients such as potassium, iron or phosphorus for entry through the plants’ root cells. As a result, plants can start to suffer from deficiencies of such nutrients, even if they are present in the water in good concentrations. For example, calcium and magnesium have the tendency to block the entry pathways of iron through root cells. Plants then start to show symptoms of iron deficiency such as yellowing leaves and short stunts.
2. Alkaline pH Levels
It is usually safe to say that hard water is alkaline (pH above 7). A number of aquatic plants thrive under alkaline conditions, but most popular species prefer neutral to slightly acidic pH. Your hardwater fish and plants might struggle, grow slowly, or even perish if you allow the pH to rise. Stabilising your pH to acceptable levels will again become very important when it comes to hard water.
3. Calcium Buildup
As will be discussed below, calcium in the tap water deposited on the plant leaves and surfaces of equipment can collect as a rocklike substance in hard-water aquariums. When present as a white crust, it reduces the penetration of light to plants. Over time, it impedes photosynthesis through poor light capture, sometimes weakening plants so they die or grow in strange ways. Cleaning of leaves and surfaces of equipment is required quite frequently to prevent calcium deposition from reducing plant vigour.
4. Algae Growth
Another reason hard water is not a great environment for plants is that it can promote algae growth because of its mineral content. With the right light and nutrients, virtually all algae passively float wherever there is food and light, which is why algae can take over an aquarium. The aquarium that many people strive for – one of green, lush plants providing a soothing habitat for their fish – is a paradise not only for plants and fish, but for algae as well. Algae can outcompete plants for nutrients and light, and the hard water simply serves as a fertiliser. It’s challenging to keep an aquarium healthy in hard water because of the issues surrounding algae.
Choosing the Right Aquarium Plants for Hard Water
But don’t worry, there are still many hardy plants that do well in hard water, so you don’t need to stress too much about the type of water you have. Just select plants that would naturally be found in hard water and your aquascaping adventures will be much easier and lower maintenance. Below are a few popular hard water plants:
1. Anubias
Anubias species are hardy plants good for hard water that don’t require spotless water, don’t grow upwards, and are very forgiving of low light. These adaptable plants are slow-growing and easy-care plants that are suitable for beginners. They can be attached to driftwood or rocks; and, due to their hearty nature, they are used in almost all aquarium styles.
2. Java Fern (Microsorum pteropus)
Another Java Fern is aptly named because its ability to thrive in hard water makes it a great option for tanks using normal municipal water as a source. Tolerance for a wide range of water parameters (even alkaline water) makes it a joy for the beginner aquarist. It can tolerate low to moderate light levels and require no maintenance.
3. Vallisneria
The best species for those with hard water are particularly attractive – among them, eelgrass (vallisneria): An example of eelgrass As its common name may give away, this stuff usually grows long and whole, producing thick ribbons of leaves that spring out from one single point, coiling out like seaweed when submerged, till it takes over the whole wheel – the background area in your aquarium.
4. Cryptocoryne
Cryptocoryne species are diverse and varied: many species actually prefer high levels of hard water! Most of these plants can deal with a wide range of light — making them a particularly easy-care plant that you can have in both foreground and midground. Some species carry interesting colours, while others have the appealing look of blobs dangling midwater.
5. Hornwort (Ceratophyllum demersum)
Hornwort is a fast-growing, floating plant that can uptake excessive nutrients from the water, minimising the chance of algae blooms. Hornwort can also thrive in hard water and doesn’t require substrate planting, which makes it a versatile choice for many different tank configurations.
6. Sagittaria
Sagittarias are very tough plants that can handle hard water. They work well as foreground plants, and may grow thick postcover if conditions are right. They are tolerant of high and low lighting.
Strategies for Managing Hard Water in Aquariums
Choosing hard-water-tolerant plants is just the first step, however – there are other strategies that aquarium keepers can use to help manage hard water conditions.
1. Water Conditioning
Water conditioners can help to combat the effects of hard water by neutralising acids and the discharge of minerals while maintaining an appropriate pH level. A water conditioner specifically designed for the hard water filtered down to your aquariums can help to grow plants and health fish. Monitoring and adjusting the water parameters are vital to keep it stable.
2. CO2 Injection
Carbon dioxide (CO2) can be added to an aquarium to make the water more acidic (ie, lower the pH), which allows more plants to thrive, or to add an element of photosynthesisful for plants and fish.
3. Reverse Osmosis (RO) Water
By using reverse osmosis (RO) filtration, a significant part of the water hardness due to the dissolved salts can be removed. To achieve a better balance, which in my opinion would make it easier to maintain stable water conditions, by lowering the total mineral content, one can add RO water (third box) to the tap water (second box). RO systems are quite expensive and often require regular maintenance.
4. Peat Filtration
Peat filtration (viewed) helps to soften water naturally, by releasing tannins and other organic acids into the water which lowers the pH as well as hardness. Peat can be added to a filtration system or directly into an aquarium substrate. Peat filtration is at best a natural level and at worst a contaminant passing through the system to really stink up the water. The water is stained with a brownish colour that many aquarists consider unsightly.
5. Regular Water Changes
With hard water, regular water changes become even more crucial. By removing a portion of the aquarium water once every one to two weeks and replacing it with fresh, conditioned water, you can keep minerals from continuing to accumulate and slowly drive the aquarium’s water parameters out of range. You also will be leveraging every water change to remove accumulated waste products and toxins that would otherwise stress plants and fish.