Review: TNC Plugs aquarium substrate fertiliser


For the first time this year a company has produced a product with packaging that doesn't make me cringe, says Nathan Hill.

Absolutely waffle free and with no hyperbolic claims, The Nutrient Company tells me exactly what I need to know without having to dress up labels with fanciful, meaningless words.

Other companies take note — this is exactly what we fishkeepers want.

TNC plugs are a capsule-based substrate fertiliser and come with a complete breakdown of exactly what’s in them. Sodium, potassium and phosphorus rank highest (15%, 4% and 9% respectively) followed by magnesium, Iron and some other trace elements.

Dosage is straightforward. Place two to four capsules per square foot of substrate at a depth of at least 4cm/1.6” and let them do their thing.

Pending planting density, these will sit there providing nutrients for six months or more.

Here they function as a standalone for slower growth or, if combined with a water-based fert, will help offer a complete growth package. After all, what’s really required for good aquatic plant growth is a mixture of both waterborne and root-based feeding.

These are just the ticket for the plant keeper who hasn’t the money to invest in nutrient-rich planting substrates, or for someone already committed to sand or gravel for aesthetic purposes but still wants plants to grow.


Excellent. Aquascapers with exhausted planting substrates will want some, community aquarium keepers with a few plants will want some, biotopers wanting to keep clusters of growth alive without weekly or daily dosing will want some — and they’re very cost effective for their anticipated lifespans.

Price: £2.96 for a ten-pack of capsules. Available from The Nutrient Company.

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