Red Sea KH Coralline Gro Supplement


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Red Sea KH Coralline Gro Supplement
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Red Sea KH Coralline Gro Supplement

Red Sea KH Coralline Gro Supplement

  • Promotes coralline algae development.
  • Should be used during the cycling of all new marine aquariums and on an ongoing basis in fish-only or soft corals systems.
  • A complex of carbonate buffers, potassium, and trace elements such as iron
  • 1ml will raise the Alkalinity level of 100L by 0.1dKH (0.03meq/L)
  • Sold in 500ml bottle 

Red Sea's Marine Care program includes an array of easy to use tests as well as an alkalinity supplement, all of which are highly beneficial for the ongoing maintenace of marine fish only systems as well reef aquariums. 

In a fish only system small weekly water changes will help to maintain the correct balance of all elements in the aquarium except alkalinity. The other main concern in these systems is to keep algae nutrients (nitrate and phosphate) under control in order to prevent outbreaks of unwanted algae. However some aquarists wish to encourage the growth of some algae, specifically coralline algae which will require the replenishment of a few specific trace elements in order to flourish. 

Coralline algae is the red/purple algae commonly found on aquarium live rock, it will spread and grow naturally without any kind of extra supplementation in all reef systems that have been optimised for hard corals. Red Sea's KH Coralline Gro is a complex of carbonate buffers, potassium, and trace elements such as iron, which are mixed in the preferred ratio taken up by coralline algae. 

To promote coralline algae in fish only or soft coral aquarium systems the alkalinity needs to be maintained at approximately 3meq/L and specific minor and trace elements need to be included. 

This product should be used instead of Reef Foundation B (KH/Alkalinity) during the cycling of ANY new marine aquarium and on an ongoing basis in fish only and soft coral systems. The alkalinity level can be monitored using the Foundation KH/Alkalinity Pro Test Kit. 

1ml will raise the Alkalinity level of 100L by 0.1dKH (0.03meq/L)

Sold in 500ml bottle 

Red Sea KH Coralline Gro 500ml R22003 7290100772133

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Delivery costs for your order will be calculated during the checkout process based on your delivery address and the contents of your basket. You will only pay one delivery charge for your order. Express delivery is FREE for online orders OVER £39 unless any of the points below become a factor.

  • Some large items like aquariums, ponds and pond liners will have an additional charge of £45.00 to help offset the cost of a pallet delivery.
  • Orders containing a physical gift card will have an additional charge of £2.45 to cover the cost of materials and delivery (digital gift cards are a free alternative).
  • Orders to highlands, islands and Northern Ireland may incur an additional delivery charge displayed at checkout this is based on the postal code provided. DPD provides a list of postal codes which have additional surcharges. Some of these post codes may also take 2 working days to arrive, even on express. Pallet deliveries cannot be sent to these post codes.

We only ship to the UK and cannot ship internationally.

We aim to dispatch items that are currently in stock on the same working day if they are ordered before 2.45 pm (excluding Bank Holidays). Orders after 3pm will be dispatched the following working day, unless it fits any of the below criteria:

  • Orders containing live plants will take up to 2 weeks to arrive. We take a week's worth of customer orders and then inform the plant farms of the specific quantities we need to fulfil that week's order to avoid wastage.
  • Pallet orders containing large items like big aquariums will take additional time to arrive as they are sent by a third party. These orders will NOT be dispatched until we have been in touch to arrange a delivery date, this is to ensure someone is available at your address to sign for the delivery. Deliveries will generally be delivered ‘curb side’ within the terms of the agreement we have with our couriers so you will need to make arrangements to transfer larger items into your home yourself. Unfortunately, our drivers are not insured to transfer the aquarium into your home.
  • Physical gift cards and items from the gift shop (such as clothes, towels etc) are sent with 1st Class Royal Mail. Delivery usually takes 1-2 working days, though in rare cases and orders placed closer to public holidays (Christmas, Father’s day, Mother’s day etc.) may be longer.


If you are not 100% satisfied with your purchase online from our website, you can return the product and get a full refund or exchange the product for another one, for up to 21 days from the date you purchased it.

We strongly suggest signing up for an account with as this will allow for some additional returns options like return to your local store.

If you checkout as a guest you will need to return the product to Maidenhead Aquatics, PO Box 619, Egham, Surrey, TW20 2BS, please package the order (along with a packing slip or a note including your name, address and order number).

Large pallet items like aquariums are deemed delivered successfully with no damage once the the driver has left the property. If a report of damage is submitted after the driver has left we may be unable to assist with replacements. We recommend refusing a damaged delivery, this is the fastest resolution.

Our full terms and conditions can be found here. When you place an order with us online you are agreeing to these terms and conditions.

For delivery before Christmas, orders must be placed on or before 3pm on Wednesday 20th December. We cannot guarantee delivery of these orders pre-Christmas as we are reliant on our couriers, but will use our best endeavours to get orders placed on this date out to you before Christmas. For full details of our festive delivery and opening times click here

Please note: online orders placed after 3pm on Friday 22nd December will not be dispatched until the New Year. For full details of our festive delivery and opening times click here