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Harvesting Oysters - Southern Ireland18th Century window showing shucking oysters
pH Correction Media - Natural Oyster Shells
Product Code: 8946PH

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Price per pack£34.80£32.40£31.68Click to View
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Sea bleached and dried oyster shells offered to naturally achieve pH balance in ponds and a rough surface for active biofilm development.

Pack Size: 15kg

Shell size: Generally between 5-7.5cm in length.
The number of shells can vary but as a working guide 1kg is likely to contain approximately 40 to 50 shell pieces.

Description and Application:
Sea washed and dried natural oyster shells with a calcium carbonate content CaCO3 in excess of 96%

These shells are the Japanese (Pacific) Oyster which have been used extensively in that country to naturally achieve pH balance in Koi ponds. The shell's rigidity, biological stability and rough surface provides an ideal alternative to plastic substrate for active biofilm development.

Source: Oysters are one of the most widely farmed shellfish in the world - our shells are recycled from established food sources.

Background: Oysters are bivalve molluscs which live by filtering plankton in marine and brackish waters. Many varieties of oyster are prized foods being rich in zinc and other minerals.

Oysters in History: The Kent coast has been noted for its Oyster beds since Roman Times. Not only did the Romans eat the meat but the shells were burnt to form a very effective cement.

As our additional image shows, in the 19th Century oysters were seen as an inexpensive food by the working classes.

* Specialist Aggregates' Price Promise:
All prices shown include UK VAT and delivery to 90% of UK locations - Read More. - There are no hidden charges on checkout.

We export throughout Europe and Worldwide - please enquire for shipping rates.

Quick Contact:
WhatsApp your enquiry and images to 07484 022898

Colour & Form:
We take great care to provide accurate images, however, as a totally natural product shade variations and irregularities can occur, we consider these add to the fascination of the collection.

Rocks in a Box For protection and security your product will be shipped in a weatherproof pack within our easy-to-handle double walled cardboard box.

Boxes are delivered by national couriers. Please advise during checkout or contact our office if you have specific delivery requirements or concerns.

Both the inner plastic pack and the outer box can be recycled via normal household or industrial/commercial collections.

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by Richard Williams Date Added: Thursday 29 September, 2022
These are specially advertised for use in Koi ponds....I own a company called Warwickshire Koi, hence my purchase. The shells are good quality but it was a shame I found hundreds of plastic ties (obviously from the oyster farm) in the bags and even more annoying was rusting bottle caps which would harm Koi. If these are advertised for Koi, they should be safe for Koi. It took me hours to remove all the crap from the mix and that was just one box. I ordered half a pallet so not looking forward to the next lot!
Rating: TEXT_OF_5_STARS [2 of 5 Stars!]
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