2Hr Aquarist APT 1 – All-In-One Liquid Fertilizer (No Nitrates or Phosphates)

What is 2Hr Aquarist APT 1?

2Hr Aquarist APT 1 (also labeled APT 1/Zero) is a nitrate- and phosphate-free liquid fertilizer for planted aquariums, built for tanks where fish outnumber plants, or for new aquascapes running on nutrient-rich aquasoil during their first 1–3 months. It supplies potassium, magnesium, iron and a full set of chelated trace elements — everything plants need except the two nutrients your fish and substrate are already producing in excess.

Skip APT 1 and keep dosing a standard "complete" fertilizer in a fish-heavy tank, and you're usually just feeding algae. APT 1 exists to close that exact gap.

Why fish-heavy and new tanks need a different fertilizer

Every fish meal that gets digested turns into ammonia, then nitrate. Every gram of aquasoil releases phosphate and ammonium as it breaks in. In a community tank stocked the way most people actually stock them, that's already more nitrogen and phosphorus than your plants can use. Layer a standard all-in-one fertilizer on top of that surplus, and the extra nitrate and phosphate don't disappear — they sit in the water column until algae find them first.

APT 1 is formulated around that reality. Same mineral backbone as APT 3, the brand's flagship all-in-one — potassium, magnesium, iron, boron, copper, manganese, molybdenum, zinc — with nitrogen and phosphorus deliberately left at zero.

Key benefits

• Zero nitrate, zero phosphate — feeds plants without adding to an already-full nutrient bucket
• ~3x more concentrated than typical off-the-shelf liquid fertilizers, dose for dose
• Chelated for wide pH bioavailability (EDTA/DTPA/EDDHA iron blend) — stays absorbable in both soft and hard water, instead of locking out
• Shrimp-safe at the recommended dose
• No CO₂ injection required — built for low-tech setups
• Calibrated pump included — 1 ml per press, no guessing

Guaranteed analysis

Who should use APT 1

• Community aquariums where fish outnumber plants
• New aquariums in their first 1–3 months, especially on aquasoil
• Low-tech tanks running without CO₂
• Tanks with a history of algae from nutrient excess

Once plants start outnumbering fish, or your aquasoil's initial nutrient release tapers off (usually 8–12 weeks in), that's your cue to move up to APT 3 — the complete NPK version in the same range. Running a high-tech, Estimative Index–style setup? APT Complete is the next step instead.

How to dose APT 1

1. Dose 3 ml per 100 L of aquarium water, daily (1 pump press ≈ 1 ml)
2. Pair with a 30% weekly water change for best results
3. A 300 ml bottle lasts roughly 3 months in a 115 L (30 gal) aquarium

Expert tip

In a fresh aquasoil setup, resist the urge to add extra nitrate or phosphate even if growth looks slow at first. The soil is already releasing both as it settles in — APT 1's job is to fill the gaps (potassium, magnesium, iron, trace elements) without tipping the tank into nutrient excess. Reassess after 8–12 weeks, once the soil's initial release has calmed down.

Frequently asked questions

What is APT 1 used for?

APT 1 is a liquid fertilizer for aquariums that already have enough nitrate and phosphate from fish waste or a nutrient-rich substrate. It supplies potassium, magnesium, iron and trace elements without adding more nitrogen or phosphorus.

Is APT 1 safe for shrimp?

Yes. APT 1 is safe for shrimp and other sensitive invertebrates when dosed as recommended.

When should I switch from APT 1 to APT 3?

Typically after the first 1–3 months in a new aquasoil setup, or as soon as plants outnumber fish and the tank needs a complete NPK source.

Can I use APT 1 without CO₂ injection?

Yes — APT 1 is designed specifically for low-tech, non-CO₂ aquariums.

What's the difference between APT 1 and APT 3?

APT 1 leaves out nitrates and phosphates and suits fish-heavy or newly set up tanks. APT 3 is the complete NPK version, built for plant-heavy aquariums where the substrate alone can't keep up with nitrogen and phosphorus demand.

How long does one bottle last?

A 300 ml bottle lasts approximately 3 months in a 115 L aquarium at the standard 3 ml per 100 L daily dose.