A little water care will prevent most problems!

Water maintenance

Water maintenance sounds a bit strange, but is in fact one of the most important maintenance measures of all, as your pond is an open system which is exposed to the weather conditions without protection. The water maintenance here covers three areas: the water treatment, the water stabilisation and the nutrient limitation.

Making the water habitable

Tap water and well water are not always ideal for pond dwellers. Tap water can contain heavy metals, such as copper, lead and zinc, especially when the water hasn’t been flowing in the domestic water pipes made of metal for some time.

Unfortunately rainwater is no longer free of pollutants. The rainwater is often collected from the roof by means of metal pipes and the pond owner believes he is doing something for the environment by supplying this water to his pond. While this is definitely a good thing to do, further metal ions can end up in the garden pond with the water which has been collected. And this is why we have the water conditioner JBL BiotoPond to treat the water for the pond dwellers.

JBL BiotoPond binds heavy metals, protects gills, skin and fins and completely neutralises dangerous chlorine, should it be present in the tap water.

An additional effect of the water conditioner is that is makes any iron, which is to be found in well water and elsewhere, available to the plants. But be careful: Don’t use well water for your pond if it contains brownish flakes or if they form after it has been stagnant for any period of time. The metal content will be too high. In general you need to thoroughly check the composition of any well water before using it in your garden pond (see the chapter water test). Depending on the area there are large fluctuations in composition and quality. Normally the iron is present in a form which the plants cannot use. Only the water conditioner’s JBL BiotoPond chelators make it possible for the plants to absorb iron.

Why do you need to stabilise your pond water?

Your tap water contains various minerals, whose quantity decides whether the water can be referred to as HARD or SOFT. These minerals not only make the water harder, they also stabilise the pH value (acidity or acid content) of your water. With a low hardness (carbonate hardness) the pH value fluctuates immensely during day and night time and does harm to your fish and microorganisms. With hardness degrees from 4 °dKH the pH level is clearly more stable and fluctuates within significantly narrower limits. Since the pH value has a logarithmic scale a reduction from pH 10 to pH 8 means a hundred fold increase of the acidic components in the water. A further decrease to pH 7 would be a thousand fold increase compared to pH 10. Therefore it is really essential to stabilise the pH value with JBL StabiloPond KH .

Since your pond is presumably not roofed-over, rainwater will enter your pond. Rainwater is basically distilled water without any minerals. The more rainwater reaches your pond water, the softer (= lower in minerals) the water will become and the more unstable the pH level will be. You can harden your pond water again with the help of a mineral mix ( JBL StabiloPond KH ) to make it pH-stable.

This is how to use anti-algae agents properly

There is yet another reason to stabilise your pond water: If you plan to use an anti-algae agent (applies practically to ALL anti-algae agents), the pH level needs to be below 8.5 where the anti-algae agents have an optimal effect. It is best to proceed as follows: Stabilise your pond water in the evening (add JBL StabiloPond KH ). Through the adding of your minerals, as well as automatically due to biological processes the pH value will decrease overnight to reach values below 8.5 the next morning. This is exactly the right time for you to add the anti-algae agent!

Here’s how to monitor your water stability

You can check the stabilisation level of your pond water at any time in just one minute: For the JBL KH Test (carbonate hardness test), drop an indicator into a cuvette, filled with 5 ml of your pond water. Then just count the drops until the colour changes from blue into yellow. The number of the drops needed to effect the colour change corresponds to the carbonate hardness of your pond water. With values below 4 you should add JBL StabiloPond KH . For values above 4 your water is stable and no action is needed.

As an alternative to the single KH test, there is also a double test that provides each pond owner with a quick, simple and precise statement on the KH and pH value: the JBL ProAquaTest PondCheck. In two cuvettes with 5 drops each of reagent, you can determine the pH of the pond water in one cuvette, and on the basis of the resulting colour, you can check whether the pond water has the required minimum carbonate hardness of 5 ° dKH in the second cuvette.

Here’s how to steal food from the algae

Limiting algae nutrients

There are two reasons why algae grow: they receive light and nutrients. In winter nutrients are available but there is a lack of sufficient light. In spring especially enough nutrients are available, there is sufficient light, and the algae start to grow. You can’t do anything about the light, so you’ll have to work on the nutrients. Phosphates are the main nutrients for algae. If you remove them from the pond water, the algae will die of starvation. This is a very efficient method.

Second option: You use an anti-algae agent to kill off the algae. But what happens after the algae have died off? The nutrients which have been stored in the algae are released into your pond water again! This way the dying algae generation fertilises the next algae generation and you are back to square one. That’s why we strongly recommend you remove the phosphates which have been released!

Here’s how nutrient limitation works

Up to 15 kg algae can theoretically arise from about 1g of phosphate. JBL has two products in its range to bind phosphates.

JBL PhosEX Pond Filter

Phosphate remover for pond filters

  • For pond water to suit both fish and plants: granules to reliably remove the algae nutrient phosphate from the pond water
from 20,96 €

JBL PhosEX Pond Direct

Phosphate remover for ponds

  • For pond water to suit both fish and plants: reliable removal of algae nutrient phosphate from the pond water
from 11,46 €

For ponds with a pond filter

If you have a pond filter in operation you can use JBL PhosEX Pond Filter for year-round use in the filter. We recommended you start using this special filter material in spring to limit upcoming phosphate values from the start. 500 g JBL PhosEX Pond Filter work for about 3 months and are able to absorb 25,000 mg phosphate.

For ponds without a pond filter

If you don't have a filter, or your filter can’t be equipped with special filter media or you have already successfully carried out treatment against algal infestation, you can use JBL PhosEX Pond Direct . 500 ml of this liquid phosphate remover binds 22,500 mg of phosphate and is sufficient for 10,000l of pond water.

We recommend you test the phosphate value of your pond water BEFORE you use a phosphate remover. That way you will know its precise initial value in your pond water. If you then use a phosphate remover you can keep track of exactly how greatly the phosphate level decreases in the water and you can estimate when to stop the phosphate removal. If, for instance, the phosphate input through food and leaves is too high, the phosphate test would indicate that the phosphate remover can’t manage this and that you need to fine-tune the food quality (good food reduces the water pollution) and leaf fall (leaf protection net, leaf removal by mechanical means).

Please keep going!

Stopping means losing the battle against the algae!

The third step of the JBL 1-2-3 algae-free concept consists of the nutrient limitation described above. Please don’t stop after the anti-algae treatment in step 2 when the algae die off! Just after that you need to start the most important step of nutrient limitation!

Combating algae

Do you have green water or thread algae? We’ll give you long term solutions for algae problems

A word about cookies before we continue

The JBL Homepage also uses several types of cookies to provide you with full functionality and many services: We require technical and functional cookies to ensure that everything works when you visit this website. We also use cookies for marketing purposes. This ensures that we recognise you when you visit our extensive site again, that we can measure the success of our campaigns and that the personalisation cookies allow us to address you individually and directly, adapted to your needs - even outside our website. You can determine at any time - even at a later date - which cookies you allow and which you do not allow (more on this under "Change settings").

The JBL website uses several types of cookies to provide you with full functionality and many services: Technical and functional cookies are absolutely necessary so that everything works when you visit this website. In addition, we use cookies for marketing purposes. You can determine at any time - even at a later date - which cookies you allow and which you do not (more on this under "Change settings").

Our data protection declaration tells you how we process personal data and what purposes we use the data processing for. tells you how we process personal data and what purposes we use the data processing for. Please confirm the use of all cookies by clicking "Accept" - and you're on your way.

Are you over 16 years old? Then confirm the use of all cookies with "Noticed" and you are ready to go.

Choose your cookie settings

Technical and functional cookies, so that everything works when you visit our website.
Marketing cookies, so that we recognize you on our pages and can measure the success of our campaigns.

PUSH messages from JBL

What are PUSH messages? As part of the W3C standard, web notifications define an API for end-user notifications that are sent to the user's desktop and/or mobile devices via the browser. Notifications appear on the end devices as they are familiar to the end user from apps installed on the device (e.g. emails). Notifications appear on the end user’s device, just like an app (e.g. for emails) installed on the device.

These notifications enable a website operator to contact its users whenever they have a browser open - it doesn’t matter whether the user is currently visiting the website or not.

To be able to send web push notifications, all you need is a website with a web push code installed. This allows brands without apps to take advantage of many of the benefits of push notifications (personalised real-time communications at just the right moment).

Web notifications are part of the W3C standard and define an API for end user notifications. A notification makes it possible to inform the user about an event, such as a new blog post, outside the context of a website.

JBL GmbH & Co. KG provides this service free of charge, and it is easy to activate or deactivate.