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Fluval Flex 123L Aquarium Only (Black) - Charterhouse Aquatics
Fluval Flex 123L Aquarium Only (Black) - Charterhouse Aquatics

Fluval Flex 123L Aquarium
£369.99

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Tax included. Shipping calculated at checkout.
0% Finance from as little as £86.68 per week. Loan terms up to 60 months also available at 14% APR. Full details here
  Free Pallet Delivery This product qualifies for free next day pallet delivery.
  Choose your delivery date  Select when your aquarium is delivered.
  Aquarium Builder Offer  Save 10% on Filtration, Lighting, Pumps.
  Earn 346 Charterhouse Points with this purchase.

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AQUARIUM BUILDER

Did you know? Buy this tank and save 10% on everything it needs

While the Fluval Flex 123L is in your basket, everything in the categories below is 10% off. We've picked the best matches for this tank in each one, or shop the whole range.

Best matches for the Fluval Flex 123L

Shop all 36 Heaters
  • Best matchAquael Ultra 150 WAquael recommends the 150 W for 90–150 L; this tank is 123 L£32.04 £35.61 with this tank £32.04 £35.61 with this tank
  • Fluval T-Series 150 WFluval rates the T-150 for tanks up to 150 L; this one is 123 L£21.14 £23.49 with this tank £21.14 £23.49 with this tank
  • Fluval E Series 200 W200 W for the 123 L tank, so it never runs flat out£40.59 £45.11 with this tank £40.59 £45.11 with this tank

Thoughtfully paired

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Reviews

Reassuring to use an operator with tracked named-day delivery, exactly what you want when dealing with glass aquariums. Great range, great prices.

Tim England

Tim England

★ ★ ★ ★ ★

24hr delivery of a pallet, for a complete marine aquarium. And two days before Christmas. No picking errors, best pricing and then great service with hour slot from UPN Pallet Network. Impressive!

Steve Lesson

Steve Lesson

★ ★ ★ ★ ★

Super happy with the tank, no issues whatsoever. The delivery was super fast too. (On the day of the delivery the delivery driver was absolutely amazing btw) Honestly cannot recommend enough 👌

Jonas Wolf

Jonas Wolf

★ ★ ★ ★ ★

Nice searchable website, plenty of stock, reasonably priced next day delivery, well packaged. Slightly more detail would have been nice as I bought 32mm thinking that was the external diameter but I suspect most people buying these items would know that. :)

Jake

Jake

★ ★ ★ ★ ★

This was actually my first time ordering something from them wasn’t sure on how long I would get it said two days, but literally I ordered it and it came the next day. Packaging was amazing. Didn’t even pay next day delivery and I got the next day If you’re reading my review, give them a try. They don’t disappoint.

AJ

AJ

★ ★ ★ ★ ★

Such a great service. Bought a fish tank Ciano emotions 150 Pro and it's arrived very well packed just 2 days after purchase. After 2 weeks i had an issue with light power supply which has been replaced straight away after I reported that to customer service. They look afyer customers and always replied very quickly if you have any problem. Strongly recommended!!!

Mr NotYour Business

Mr NotYour Business

★ ★ ★ ★ ★

Received my tank on Friday the 13th absolutely perfect driver was really really good dropped it right outside my little doorstep because it was on the path. Very very pleased with my purchase tank is looking absolutely fantastic. Will definitely use you again absolutely brilliant thank you.

Alan Ogden

Alan Ogden

★ ★ ★ ★ ★

Just received another delivery from Charterhouse aquatics, this time salt and frozen food: best price, all info I needed and free delivery that is quick and quality. Keep up the good work. And I love the reward scheme too!

Joyce Maturana Ferres

Joyce Maturana Ferres

★ ★ ★ ★ ★

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CHARTERHOUSE REWARDS

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Points with every eligible purchase8 stamps. 10% off.

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1. Shop and earn points

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

02

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

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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.

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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.