Aquarium Plant Fertilizer

For high-light tanks, add 1 tsp per 10 gallons 1-2 times a week; for low-light tanks, 2-4 times a month. Add it near the filter outflow or another high-flow area so it mixes through the tank. High light drives faster plant growth and faster nutrient use, so brightly lit tanks need more frequent dosing, while low-tech tanks need much less. Dose by your tank's actual water volume, accounting for substrate and hardscape displacement.

At 1 tsp per quart, the 8 oz bottle makes about 48 watering cans of feed. For a typical shelf of 10–15 plants fed every 1–2 weeks in season, that's several months of feeding — and the 32 oz bottle four times that.

It's a plant fertilizer formulated for the low nutrient levels a planted tank needs, so used at the labeled rate it's intended to be safe alongside fish. Stick to the dose and don't overdo it — sudden nutrient spikes stress any tank. One caution for shrimp keepers: this contains copper at trace levels, and some invertebrates are sensitive to copper, so introduce it gradually and observe. As with any additive, dose to the water volume and avoid pouring it directly onto livestock.

Overdosing can, since algae compete with plants for the same nutrients — but in a planted tank, algae is more often driven by a mismatch between light and CO2 than by fertilizer alone. Too much light without enough nutrients or CO2 for the plants to use it is the classic algae trigger. This low-concentration blend is designed to feed plants without loading the water, but the real algae control is balancing light, CO2, and nutrients together, plus regular water changes.

No — this works in both low-tech tanks without added CO2 and high-tech tanks with it. In a low-light, no-CO2 tank, plants grow slowly and need only occasional dosing, which this covers with the 2-4 times a month schedule. In a high-light tank with CO2, plants grow fast and use nutrients quickly, so you dose more often. CO2 boosts growth but isn't required; match your dosing frequency to your tank's light and growth rate.

In a well-lit tank, aquarium plants respond over a few weeks with stronger new growth and better color, especially as they take up iron and potassium. Fast-growing stem plants show it first; slower rosette plants and carpets take longer. Existing damaged leaves won't recover, so you're feeding new growth. Results depend as much on light and CO2 as on nutrients, so a balanced tank shows the clearest improvement.