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Oase BioMaster External Filters

The BioMaster external filters fulfil the highest demands of water filtration and filter cleaning. The combination of highly effective biological filtration by Hel-X and mechanical-biological cleaning by filter sponges ensures healthy and clear aquarium water.

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Discover Oase External Filters at Charterhouse Aquatics

Oase external filters are trusted by aquarists worldwide for their powerful multi-stage filtration, quiet operation, and long-term reliability. Whether you’re running a small planted aquarium, a large freshwater community tank, or even a marine setup, Oase filters deliver crystal-clear water with minimal effort. The innovative EasyClean pre-filter module reduces maintenance time, while models in the BioMaster² Thermo series feature an integrated HeatUp heater, keeping your aquarium clutter-free and perfectly regulated. At Charterhouse Aquatics, you’ll find the full range of Oase BioMaster, BioMaster² Thermo, and FiltoSmart filters, along with replacement sponges, Hel-X biological media, and accessories to keep your system running at its best. Enjoy fast UK delivery, competitive prices, and expert support when you shop with us. Invest in an Oase external filter today and experience a cleaner, healthier, and easier-to-maintain aquarium.
Discover Oase External Filters at Charterhouse Aquatics

CHARTERHOUSE REWARDS

A little thank you, every time.

Earn points when you shop, then turn them into money off at checkout.

Points with every eligible purchase8 stamps. 10% off.

COLLECT POINTS

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Earn automatically on eligible product spend after discounts, excluding delivery.

SPEND POINTS

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Switch on your points at checkout to save on eligible products.

Normal value: 100 points = £1 off. Flash offers can increase this.

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How to earn and spend your points

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1. Shop and earn points

Earn 1 point for every £1 of eligible product spend after discounts, excluding delivery.

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2. Use your points at checkout

Sign in at checkout and switch on “Use my points”. Your available points become money off automatically—no voucher to claim. Savings cover eligible products only; any points you cannot use stay in your balance.

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3. Get more with flash offers

Watch for flash offers with double or triple points, or extra value when you spend them.

YOUR STAMP CARD

Eight stamps. One lovely thank you.

Each order with £250 or more in products after discounts, excluding delivery, earns one stamp. Fill all 8 slots to unlock a 10% off code, valid for 365 days. Use it alongside your points.

Sign in to see how close you are to your next reward.

Good to know

Why are some points pending?

Purchase points have an approval period before they become available. Your balance shows available points separately from pending points.

How long do my points last?

When points expiry applies, your balance stays valid for 365 days from qualifying rewards activity. Earning eligible rewards, redeeming points or a balance adjustment renews that window. Simply visiting the shop does not renew it.

Can I use points with my stamp reward?

Yes. Add your 10% stamp reward code at checkout and switch on your points. Your final saving depends on the eligible product total and any other discount restrictions.

What happens if I return something?

Earned points are adjusted for returns. Points used on refunded products are restored proportionally. If a refund takes a qualifying order below £250, its stamp is removed.

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