Hydra Black Liquid Dye
 Hydra Black Liquid DyeHydra Black Liquid Dye 

Hydra Black Liquid Dye

Our Price:  £11.95
List Price:  £14.00
Saving Of:  £2.05 (15%)
(Inc. 20% VAT)(£9.96 Exc. VAT)
Pack Size:

To preserve colour, use with Hydra Aqua-Brite

See all Hydra Water Dyes

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  (12 Reviews)
  • Works in all ponds and water features, small or large
  • Adds a reflective mirror finish within water features and/or ponds
  • Environmentally friendly and non-toxic
  • Very economical to use
  • Safe for fish, birds, and other wildlife
  • Stops light from reaching the bottom; Reduces or halts algae/weed growth
  • Free of pesticides and herbicides
  • Up to 3 years shelf life

Brand:  HYDRA



  • Works in all ponds and water features, small or large
  • Adds to the reflective/mirror quality within water features and/or ponds
  • Environmentally friendly and non-toxic
  • Very economical to use
  • Safe for fish, birds, and other wildlife
  • Quick and simple application
  • Aesthetically appealing
  • Free of pesticides and herbicides
  • For all-year-round use



Hydra Black Liquid Dye provides an impressive reflection to your pond and/or water feature and has been used by the likes of landscape gardeners, garden pond/water feature keepers, local authorities, golf courses, and farm ponds. We have also known our dyes to be added in small amounts, to glass vases and centrepieces for weddings and other events, to create more drama and atheistically appealing looks.

With its quick dispersion quality and high concentration, its usage, even in low quantity, is enough to enhance the aesthetic appeal of your pond or water feature by creating a mirrored surface. It safely protects and shades your pond or water feature in a black colour.

Hydra Liquid Dyes are environmentally friendly and non-toxic, meaning they will not harm birds, reptiles, mammals, or fish. So, if you have fish with your pond, adding dye to your pond will not affect them or their health, if anything, the dye will help to protect them. Dye used within ponds with wildlife within will help deter predators, for example, fish will be protected from the predators such as herons.

Water from ponds and water features that have been dyed with any Hydra Liquid Dye is safe to use as part of irrigation of crops, meaning, if you wanted to change the water in your water feature, for example, you can empty it onto your flowerbeds and they will not be affected.


Liquid dyes all work in the same way as food colouring; It dyes something in your required colour. However, liquid dyes used within ponds and water features offer an additional benefit in that they can help reduce plant and algae growth. Dyes do not, however, hinder the growth of all aquatic plants, they are recommended for submerged plants such as pondweeds, watermilfoil, and elodea, as well as plants such as water lilies.


The Problem Pond weeds, like all plants, algae and many bacteria, use the energy from sunlight to convert carbon dioxide into organic compounds, most typically, sugars.

Without sunlight, photosynthesis could not occur and life as we know it could not flourish. Because they can synthesize food directly from carbon dioxide using light energy, pond weeds are classified as photoautotrophs. Most appear green in colour due to the light-collecting pigment known as chlorophyll-a.

The Solution Hydra Black Liquid Dye is very effective in prohibiting all types of pond weeds and algae’s. By using a non-toxic colorant in the water, you can partially filter sunlight, thereby thwarting the photosynthetic process for many aquatic weeds and algae. 

Remember it is easy to add extra dye but impossible to remove dye from water. The water will have to be retreated as required this will depend on rainfall and other localised conditions.

Usage Rates:

  • 5ml treats up to 21 litres (4.6 gal).
  • 25ml treats up to 106 litres (23 gal).
  • 250ml treats up to 1,063 litres (234 gal).
  • 500ml treats up to 2,125 litres (467 gal).
  • 1 litre treats up to 4,250 litres (935 gal).
  • 5 litre treats up to 21,250 litres (4,670 gal).

Factors to take into account:
Water temperature and degree of agitation will influence speed of dispersion. The original water colour will effect the final colour. Before adding more dye to increase colour density, wait at least 24 hours to ensure that original dye is fully dispersed.

* Please note that all the images used are for illustrative purpose only. The actual colour may differ as it depends upon the pond water condition.


How to use

Administering dye to your pond or water feature is as simple as pouring the correct measurement needed of dye into the water. It will quickly disperse within and around the pond and/or water feature, meaning no need to spray or spread the application yourself.

Where to use

Water dyes can be applied to ponds and water features of any size, small or large.

Not only can water dyes be added to ponds and water features, they have also been known to be used in small amounts, to glass vases and centrepieces at events and weddings to create drama and aesthetically appealing looks.


NOTE – Use Hydra Aqua-Brite with Hydra Powders and Liquid Dyes. Do not use with chlorine or any other product unless specified by Hydra International Ltd.

Can I use this dye if I have fish in my pond?

Yes. Hydra Liquid dye is food grade dye, and it is completely safe for fish, plants and invertebrates.

My dog sometimes drinks water from my pond. Will it be okay?

Yes, absolutely. Dogs, cats, birds, wildlife - this food grade based dye is safe to be used for drink.

Although, if your dog often drinks pond water - be aware of Blue Green Algae

What happens if we put too much pond dye in our water?

The water will be a deeper shade, and possibly opaque. Over time, rainfall will dilute the colour to the point where it will all be gone. You can also add more water, or partially change water to dilute dye. If emptying the pond is required, the water should be flushed into soil beds – please avoid letting over dyed water get into surface drains or streams. Any water getting into a stream or drain will not be harmful, but it might concern other people if they see odd colour in flowing water - they might report it to authorities as ''pollution''. 

Can water dye leave stains?

Yes, but nothing that can't be washed. It will most likely stain your hands and clothes - that's why it is recommended to wear gloves and protective clothes when using our product. Also, when diluted - it might stain the rock or surface where the water touches, but it is nothing permanent - sunlight will fade any residue.

Is pond dye a good idea?

There is a range of benefits to using pond dyes other than changing the aesthetic of your pond or lake. Pond dyes will limit the sun exposure, promote a balanced ecosystem within your pond or lake and also protect the wildlife living in your pond.

Will pond dye get rid of algae?

Although dyes will not get rid of algae it will reduce the sunlight penertration, this will then reduce the growth becuase it slows the effect of photosynthesis.

How long does dye last in a pond or lake?

Pool dye will last between 4-8 weeks on average depending on your weather.

When should i add the dye to the pond?

To have the best effect and year long benefits you should apply the dye in early spring and then continue to apply every 4-8 weeks depending on rainfall.

Can you swim in a pond that contains pond dye?

Once the pond dye has completely mixed with the water, its is safe for swimmers to jump in, there is no need for you to worry about dying the colour of your skin.

Can we use more than recommended?

Absolutely! Our recommendation is top maximum that our dye can work and still be visible. Please wait 24 hours before adding more solution to the water, as sometimes it takes time for colour to 'settle in''. However, if you are using more than it is recommended - you can expect colour to be darker, more vibrant and water can seem deeper.

In case you overdo it, nothing to worry about. It will fade out with either rainfall or sunlight, or you can dilute water with adding more water or partially changing water. 

Average Rating (12 Reviews):  
Write a Review and share your opinions!

Immediate effect
01 June 2019  | 

Having only recently put in a small pond, our waterfall feature water turned green from the sun. I have been looking around for products to get rid of the green and saw Hydra Black Liquid Dye and a bonus they are near where I live. I put 20ml into the pond water and stirred it around and instantly the horrible green disappeared and the black pond liner was visible and shiny again. It doesn't stain the granite stone. I am very impressed with this product and a little goes a long way so should last a long time.


9 of 9 people found this review helpful.

Protects my koi
17 May 2019  | 

Deeep black colour hides the fish. I have been tormented by an otter recently. Hope the dark colour stops her from feeding on my fish.


5 of 5 people found this review helpful.

Fantastic deep black
19 April 2019  | 

Have used this in two water features, fantastic deep black and has not stained the fountains. The birds drink from these water features so I am happy that it is safe for them. Be careful though a little goes a long way, so under dose to start with, then if not black enough add more dye until you achieve the colour you require.


6 of 6 people found this review helpful.

Saved hours of cleaning
24 August 2018  | 

Having had major issues with algae in my pond I had been looking for an answer for ages. Came across the Hydra black liquid dye on the internet, reviews looked good so I gave it a try. Boy am I glad I did, it has saved me hours of manual cleaning I simply treat the pond in spring and autumn for lasting effect.

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8 of 8 people found this review helpful.

Perfect effect
12 July 2018  | 

Fantastic stuff. I had decided to do a project whilst in lockdown and create a water feature. I have learnt that green-ness will come along eventually even if you use clear water tablets and never turn off your pump. Today I tried the Hydra Black Liquid dye and am really happy. I used about 1ml for 300 litres of water and the effects are delightful.


4 of 4 people found this review helpful.

Highly reflective finish
04 July 2018  | 

Makes my pond highly reflective, fish don't seem to mind the colour as they are still feeding normally. On first application only add the stated dose, as in my case I found that this made it dark enough.


7 of 7 people found this review helpful.

Fantastic mirror effect
27 June 2018  | 

Gives fantastic mirror effect in my pond, really shows off the colours of my lillies.


5 of 5 people found this review helpful.

Its Amazing
21 May 2018  | 

I was unsure If I was doing the right thing but I am so glad I did, it is AMAZING! It has restored my dull and sludgy rill which I built in the back garden into a professional reflection pool. Another bonus is that it is animal friendly so I don't need to worry when the birds drink and wash from it.


5 of 5 people found this review helpful.

Heron zero, Hydra won!
18 May 2018  | 

Had major problem with Heron stealing my fish. None lost since using the hydra black liquid dye, as well as a great mirror finish to the pond. Think the heron has given up and gone elsewhere.


3 of 3 people found this review helpful.

Highly recommended
15 June 2017  | 

We have a small pond, you could see the water pump before which was unsightly. Used a tiny amount of the black liquid dye liquid and the water went totally black, pump is now hidden we are very pleased with the result.

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3 of 3 people found this review helpful.

Read all 12 customer reviews...

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