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Coco nutrients or recirculating hydroponic nutrients: which bottle fits?

Updated: October 2026

You have coir in pots, or channels returning nutrient solution to a tank, and two CANNA boxes both appear to be hydroponic feed. Choosing coco nutrients or recirculating hydroponic nutrients depends on where the roots sit and whether the solution drains away or comes back. CANNA Coco A and B is a whole-cycle recipe for coir. Aqua Flores is a flowering feed for a recirculating system. Fish-Mix is a third case, biologically active soil or coco, not a substitute tank nutrient. Start with the [hydroponic fertiliser comparison](/hub/fertiliser-soil-and-bark-mulch/hydroponic-fertiliser). It is not a laboratory trial. A qualifying purchase can earn a commission at no extra cost to you.

You have coir in pots, or channels returning nutrient solution to a tank, and two CANNA boxes both appear to be hydroponic feed.

Our top picks

BioBizz BioBizz Fish-Mix, 1 litre

Best overall

BioBizz BioBizz Fish-Mix, 1 litre
9.4/10about £12.56
View offer
CANNA CANNA Coco A and B, 1 litre set

Rank 2

CANNA CANNA Coco A and B, 1 litre set
9.4/10about £17.56
View offer
CANNA CANNA Aqua Flores A and B, 1 litre

Alternative

CANNA CANNA Aqua Flores A and B, 1 litre
7.8/10about £23.01
View offer
On this page
  1. 1.If the roots are in coir
  2. 2.If the solution comes back to the tank
  3. 3.Fish-Mix is the third case
  4. 4.Which box to open

If the roots are in coir

CANNA Coco A and B is the choice when coir is the medium. It is one two-part recipe through growth and flowering, not an A bottle for growth and a B bottle for bloom. Add both parts at every feed, each diluted into the water first. The published full-strength direction is 40 ml of A and 40 ml of B per 10 litres, with pH 5.5–6.2 and EC 1.2–2.3 including the starting water. Those figures are a reference, not a reason to ignore plant size or the current chart. You do not swap away from Coco A and B merely because the plants move into flower. The listing was about £17.56, at 4.7 from 1,969 ratings. Reviews mention coco, a feed chart, a leak, and French on the B bottle, so keep the UK chart. CANNA also names run-to-waste and ebb and flow. That does not make this the default NFT nutrient. The wider fork is on the hydroponic fertiliser buying guide.

If the solution comes back to the tank

A recirculating system sends the solution back to the tank. CANNA Aqua Flores is for that arrangement during flowering, including NFT. CANNA describes the bloom formula as lower in nitrogen and higher in potassium and phosphorus than the growth-stage partner. That is a stage description, not an NPK figure from an Amazon field. The stated direction is 30 ml of A and 30 ml of B per 10 litres, with pH 5.2–6.2. Do not carry the Coco dose across because both products are A and B sets. Aqua Flores is not a whole-life tank feed. Aqua Vega, the vegetative partner, is not on this shelf. The listing was about £23.01, at 3.9 from nine ratings, with one stored word. Do not put Aqua Flores into coco because the tank recirculates. Coir can bind or release elements, while clay pebbles, perlite, and rockwool do not behave the same way.
BioBizz BioBizz Fish-Mix, 1 litre

Testsieger

BioBizz BioBizz Fish-Mix, 1 litre
9.4/10about £12.56
View offer

Fish-Mix is the third case

BioBizz Fish-Mix is neither the coco mineral pair nor the recirculating bloom set. It supports biologically active growing in soil and coco. The maker guidance spans 1–4 ml per litre, and the schedule moves away from Fish-Mix when flowering should start. It is not a direct alternative to Aqua Flores. The Amazon highlight includes the word hydroponics. That is not an instruction to pour fish emulsion into an NFT reservoir. Organic material can smell and can sit in tanks and lines. Fish-Mix was about £12.56, at 4.7 from 2,059 ratings, and that count does not prove it suits your plumbing. For indoor jars or LECA, use the best hydroponic fertiliser page.

Which box to open

If the roots are in coir, choose CANNA Coco A and B for the whole cycle. If a bare-root or inert system returns solution and the crop is flowering, Aqua Flores is the box, with a growth-stage feed before bloom. Fish-Mix can have a role in soil or hand-fed coco. It is not the NFT substitute. Saving about £5.45 by buying the coco set instead of Aqua Flores is no saving if the crop needs the recirculating bloom formula. Coco uses 40 ml plus 40 ml per 10 litres. Aqua Flores uses 30 ml plus 30 ml. Neither is a vague 1:1. Water-first order is on how to mix hydroponic nutrients.

Common questions

Is CANNA Coco A the grow feed and Coco B the bloom feed?
No. A and B are two components of the same coco recipe, and both are used through growth and flowering. Add A to the water and mix, then add B and mix. Never combine the concentrates directly.
Is Aqua Flores suitable for the whole life of a recirculating crop?
No. Aqua Flores is the flowering-stage formula. CANNA Aqua Vega is its vegetative-stage partner, but Vega is not included in this product folder, so you need to source a suitable growth feed separately.
Can I use CANNA Coco A and B in an NFT tank?
Do not choose it merely because the listing says hydroponic. Coco A and B is formulated around coir, while NFT normally needs a nutrient intended for a returning solution and the crop's current stage. A coco-filled ebb-and-flow system is a different case from bare-root NFT.
Why is a recirculating nutrient a poor match for coco?
Coir interacts with nutrient elements rather than behaving like a fully inert medium. CANNA warns that using a recirculating formula with coco can create deficiencies because the substrate withdraws some elements. Reservoir EC alone may not reveal that imbalance.
Can Fish-Mix go into a recirculating reservoir?
The Amazon copy uses broad hydroponics wording, but the stronger use case is soil or coco with biological activity. It is not presented here as an NFT base feed, and organic material may bring smell and maintenance issues to tanks and narrow lines.
Are the mixing rates the same for both CANNA sets?
No. CANNA publishes 40 ml of each Coco component per 10 litres and 30 ml of each Aqua Flores component per 10 litres. Use the current manufacturer chart and adjust for your plants and source water rather than transferring one set's rate to the other.

Related pages

Hydroponic fertiliser

Best hydroponic fertiliser UK, matched to the system

Hydroponic fertiliser buying guide for your system

Hydroponic fertiliser for houseplants in LECA or a jar

How to mix hydroponic nutrients without sharing charts

Sources

Public UK and maker sources used for this page in October 2026. Prices, stars and review counts are from the eight amazon.co.uk listings. Shelf date 21 October 2026. The card score is the star line times 20, not a laboratory test. No NPK is stated, because none of these listings print one. A fish-emulsion sheet is not a UK organic certificate.

  1. RHS, hydroponics (retrieved 21 October 2026)
  2. GOV.UK, manufacturing and marketing fertilisers (retrieved 21 October 2026)
  3. Fertilising Products Regulations 2020 (retrieved 21 October 2026)
  4. CANNA Aqua Flores (retrieved 21 October 2026)
  5. CANNA, ideal pH level (retrieved 21 October 2026)
  6. Growth Technology, the grower's guide (retrieved 21 October 2026)
  7. BioBizz Fish-Mix data sheet (retrieved 21 October 2026)
  8. amazon.co.uk, hydroponic nutrients best sellers (retrieved 20 October 2026)