7 Best Fertilizers for Planted Aquariums 2026

When it comes to root-fed plants, few supplements deliver with the precision and completeness of ThriveCaps. These nutrient-dense root tabs are engineered to dissolve slowly in the substrate, releasing a full spectrum of macronutrients and micronutrients—including nitrogen and phosphate, which many competing root tabs omit. For planted aquarium enthusiasts battling stunted stem growth or melting crypts, this is a game-changing fix that targets the source: the root zone.

In real-world use, ThriveCaps shine in tanks with heavy root feeders like Amazon swords, crypts, and bulb plants. Each 1-gram capsule is packed with iron-rich clay, mineralized topsoil, and dry Thrive mix, creating a localized nutrient hotspot that lasts weeks. We buried them 1–2 inches deep during planting and saw noticeable root development within 10 days, with lush, upward growth following shortly after. However, they’re not ideal for floating or epiphytic plants—this is strictly a substrate-focused solution, and overuse can lead to minor algae spikes if water parameters aren’t balanced.

Compared to Flourish Root Tabs, ThriveCaps offer a more complete nutrient profile, especially with the inclusion of nitrogen and phosphate—critical for robust rhizome expansion. While both are solid choices, ThriveCaps stand out as the best root tabs for planted aquariums demanding comprehensive nutrition. They’re particularly suited for medium to high-light tanks with nutrient-hungry flora, where long-term substrate enrichment makes a visible difference. For the performance-to-value ratio, they out-deliver in head-to-head tests against simpler, incomplete formulas.

If your planted tank runs hot and heavy—with high light, CO₂ injection, and fast-growing stems—then NilocG’s Liquid NPK+M is the nitro boost your plants have been craving. This dual-bottle system (macro and micro) delivers laboratory-grade concentration, making it a favorite among EI (Estimative Index) dosers who demand precision and consistency. With each drop, you’re feeding your aquarium a nutrient-dense cocktail that fuels explosive growth, rich pigmentation, and dense leafing—exactly what advanced aquascapers need.

During testing, we dosed a 75-gallon high-tech tank six days a week, and within two weeks, Rotala rotundifolia and Limnophila aromatica showed dramatically tighter internodes and deeper red hues. The highly concentrated formula means a little goes a long way—each 500ml bottle treats up to 2500 gallons, translating to exceptional longevity. It performs flawlessly in CO₂-rich environments but can be scaled down for low-tech use with caution. That said, beginners may find the dosing regimen intimidating, and without regular water testing, there’s a slight risk of nutrient imbalance if not monitored.

Pitted against Thrive S, NilocG lacks shrimp-specific safety tweaks but surpasses it in raw power and dosing flexibility. It’s the best overall fertilizer for planted aquariums that prioritize growth velocity and color intensity over simplicity. Ideal for experienced hobbyists running EI or similar methods, it’s a no-nonsense, high-performance system. When stacked against all-in-one solutions, it offers superior control and potency, making it the go-to for those who treat their tank like a planted lab.

For shrimp keepers walking the tightrope between plant nutrition and invertebrate safety, Thrive S is a breath of fresh water. This shrimp-specific formula delivers a full suite of macros and micros while excluding copper and other harmful elements that can devastate sensitive crustaceans. It’s the rare all-in-one fertilizer that doesn’t force you to choose between lush plants and thriving shrimp—making it the gold standard for shrimp tank fertilizers.

In heavily planted nano tanks with Neocaridina and Caridina species, Thrive S consistently promoted vibrant growth in mosses, Bucephalandra, and Anubias without triggering algae or stressing shrimp. The 500ml pump bottle treats 2500 gallons, offering excellent value, and the once-daily dosing is simple enough for beginners. It works well in both low and medium-tech setups, though high-light, CO₂-heavy tanks may require supplemental feeding. One caveat: while it’s safe for inverts, it’s not as potent as NilocG for demanding stem plants, so growth is steady but not explosive.

Compared to Thrive C, it shares a similar base but is fine-tuned for shrimp compatibility, with even stricter control over trace elements. It’s the best choice for shrimp tanks where safety trumps speed. For hobbyists who value ecosystem balance, it’s unmatched. While not the most aggressive fertilizer on the market, its safety, reliability, and ease of use make it a top contender—especially when weighed against more aggressive formulas that risk invertebrate health.

Thrive C is the unsung hero of low-tech planted aquariums, where simplicity and stability rule. Engineered for tanks without CO₂ injection, this all-in-one liquid fertilizer provides a balanced blend of micros and macros that keeps plants healthy without overwhelming the system. For beginners or hobbyists who want lush growth without complex dosing, it’s a plug-and-play solution that just works—no test kits or spreadsheets required.

We tested it in a 20-gallon low-light, non-CO₂ tank with java fern, moss, and dwarf sagittaria, and saw noticeable improvement in leaf density and color within two weeks. The 500ml bottle lasts forever—dosing just 5ml per 50 gallons weekly—and the formula is gentle enough to avoid algae outbreaks, even in tanks with inconsistent maintenance. It’s not designed for high-demand plants like HC Cuba or red rotala, but for moderate growers, it’s more than sufficient.

Against Aqua Plants All Included, Thrive C offers similar ease of use but superior concentration and longevity. It’s the best fertilizer for low-tech tanks that want reliable, no-fuss nutrition. While it can’t match NilocG in power, it excels in stability and user-friendliness, making it ideal for newcomers or maintenance-focused aquarists. For the balance of performance, safety, and simplicity, it outshines budget options without the premium price tag.

When budget matters but performance can’t be compromised, Aqua Plants All Included by Aquamins delivers a surprisingly robust punch for just a few bucks. This complete all-in-one formula covers macros, micros, and trace elements in a single bottle, making it a no-brainer for hobbyists who want value without complexity. It’s the best budget-friendly fertilizer for planted aquariums, especially for nano tanks or low-tech setups where cost efficiency is key.

In testing, it performed admirably in a 10-gallon planted tank with moderate lighting and no CO₂. After three weeks, dwarf hairgrass thickened, and Anubias leaves darkened noticeably, with zero impact on shrimp or snails. The 250ml bottle includes a clear dosing cap (1 cap = 6ml), and at 5ml per 100 liters weekly, it lasts longer than expected. It’s not ultra-concentrated like NilocG, but for the price, it’s remarkably effective. That said, in high-light tanks, it struggles to keep up with nutrient demand, and frequent dosing is needed for fast growers.

Next to Crystalpro Flora Multi Minerals, it offers better overall balance and safety, without the need for daily dosing. It’s not the most powerful, but for casual plant keepers or beginners, it’s a smart, affordable entry point. While it lacks the depth of Thrive or NilocG, its safety, simplicity, and price make it a standout. For those who want solid results without overspending, it beats pricier options in cost-per-gallon performance.

Potassium is often the silent gap in planted tank nutrition, and Aquamins Aqua Potasflow is the targeted fix that fills it. This pure potassium supplement zeroes in on one of the most common deficiencies—weak stems and yellowing leaves—and corrects it fast. For tanks with rapid stem growth or heavy pruning, it’s a must-have booster that strengthens cell walls, enhances chlorophyll, and keeps plants standing tall.

We used it in a high-light, CO₂-injected 55-gallon tank where fast-growing stems like Ludwigia and Rotala were showing pinholes and leaf drop. After two weeks of 1ml per 100L dosing, symptoms vanished, and new growth emerged thicker and greener. The formula is incredibly clean, with no phosphate or nitrogen to disrupt balance, and it’s safe for fish, shrimp, and snails. However, it’s not a standalone solution—it’s a supplement, not a complete fertilizer, so pairing it with a micro or macro base is essential.

Compared to NilocG’s macro bottle, Potasflow is more specialized but less broad. It’s the best fertilizer for leaf and stem growth when potassium is the bottleneck. Ideal for experienced users tweaking their nutrient profile, it’s a precision tool rather than an all-in-one. While it doesn’t replace a full fertilizer, its targeted strength and affordability make it a smart add-on—especially when stacked against general-purpose liquids that underdeliver on potassium.

Crystalpro Flora Multi Minerals enters the ring as a compact but potent all-in-one contender, packing a wide spectrum of macro and micro elements into a small 250ml bottle. It’s designed for fast-growing plants, delivering key nutrients like potassium, iron, magnesium, and zinc—minus phosphate and silicate, which helps prevent unwanted algae in sensitive systems. For aquarists who want rapid growth without phosphate buildup, it’s a cleverly formulated alternative to traditional all-in-ones.

In high-light, CO₂-rich tanks, it delivered tight internodes and vivid coloration in red stem plants, with daily dosing (5ml/100L) fueling aggressive growth. The absence of phosphate means you’ll need to supplement separately if your tap water is deficient, but this also makes it ideal for tanks prone to algae from excess P. It’s safe for all livestock and doesn’t cloud water, but the daily dosing requirement may deter those seeking low-maintenance options.

Against Thrive C, it’s more targeted for high-performance tanks but less beginner-friendly. It’s the best all-in-one micro & macro fertilizer for those who want control over phosphate input. While not as user-friendly as set-and-forget formulas, its customizability and growth speed make it a favorite among intermediate to advanced hobbyists. For the precision it offers in nutrient management, it holds its own against more expensive, less flexible competitors.