Do Hydra Crystals Work? How To Clear Green Pond Water With A UV Pond Clarifier
I frequently receive questions from subscribers to my free weekly news letter, asking for advice relating to their ponds or water gardening in general.
Wherever possible I will attempt to answer them using my own knowledge and expertise. Failing that I will attempt to ascertain an answer for them.
Today I would like to discuss a very common pond keeping problem. One raised by Roger, a newsletter subscriber who lives in the UK who would like to know how to avoid green algae build up…
“Hi Sean
What do you know of HYDRA CRYSTALS do they work, this year my pond keeps turning green its round 2 meters wide and a meter deep all over, little or no plants as the fish keep eating them and its in full sun. I have tried barley straw extract and keep changing half water at a time but still it changes to green pea soup.
HELP
Roger"
This is my response to Roger
"Hi Roger,
Thanks for your email.
First of all I would just like to point out exactly what it is that Hydra Crystals do...
Hydra Crystals are a mineral based 100% biodegradable method of removing green pond water algae. The nano particles within Hydra Crystals pond treatment via ion exchange absorb the nitrates and phosphates from the pond water. Nitrates and phosphates are a food source for green pond algae. Without this food source they die off.
Hydra Crystals pond treatment causes the algae cells to flocculate (clump together). The clumps eventually sink to the pond floor where your pond filter should remove them.
The manufacturers of Hydra Crystals claim that the product will clear murky, pea soup like pond water within minutes and doesn't interfere with pond bio filters, pond pumps, pond liners and concrete ponds.
In addition the manufacturers claim that Hydra Crystals pond treatment is 100% safe and harmless to pond fish, aquatic plants, frogs, snails, toads and other pond life. It is also human friendly.
Do Hydra Crystals Work?
The answer is YES but I would like to add the following comment ... IT IS A SHORT TERM FIX AND NOT AN ON GOING SOLUTION ... NOT MUCH DIFFERENT FROM USING POND ALGAECIDES IN MANY WAYS.
If you are wanting to remove green pond algae on an ongoing bases there is only one really effective cure and that is to use a correctly specified Ultraviolet clarifier (UV clarifier) often known as a UV sterilizer in the USA. Strictly speaking there are differences but in the pond keeping world you can be sure that we are all talking about the same type of product.
As water is pumped through the UV clarifier the algae cells are bombarded with ultra violet light. This kills them, causing them to clump together. These larger clumps are them removed by your biological filter as the clumps fall to the pond floor.
Any pond unless it is a bog filter (veggie filter) needs a pond pump, biological pond filter and UV clarifier. In many cases a biological pond filter includes a UV clarifier. Given the choice a combined pond filter and UV is a good choice because you can be certain that they are compatible in terms of power and size.
Many people use chemical additives, such as pond algaecides to avoid green algae build up. This is at best a short term fix and at worst it affects pond pH and beneficial pond bacteria.
Chemical treatments only work for a short period of time and will cause the formation of sludge on your pond floor, a whole new problem altogether. The algae clumps not picked up by your biological pond filter will rot on the pond floor and turn into pond sludge. As the sludge increases so will heterotrophic bacteria, eventually leading to polluted pond water and an increase in fish health problems.
My advice ... don't use any form of chemical additive for controlling green pond water. The most effective way to permanently control green pond water is to use a Pond UV Clarifier.
I notice that you say you have been using barley straw products. Barley straw is a product that has been used for many years to control blanketweed and other string algae forms ... In my opinion it is popular but no where near as effective as Viresco Aqua Or Viresco Koi blanketweed treatments.
Viresco has been designed to control string algae (blanket weed) and the build up of pond sludge. It will also control green pond water as well because it works by removing the algae food source (nitrate).
My advice though would be to use Viresco to control blanketweed build up and use a UV pond water clarifier for green pond water control.
Honestly if you are looking for a permanent solution to "How To Clear Green Pond Water" then a UV pond clarifier is the best solution as well as being cheaper in the long term because you don't have to keep replacing the Hydra Crystals (same applies to pond algaecides or other chemical treatments). You will only have to replace the UV quartz tube once a year ...
Hopefully this will help.
Regards