Usage Guide

How to get the most out of APT.

What is my tank volume?

Dose according to the Water Volume in your tank. Wood, substrate and rocks often take up 15% or more of Tank Size. Water Volume Calculator here.

How much to dose for APT1/APT3/APTe?

APT 1 & APT 3 standard dose: 3ml / 100L per day.APT e standard dose: 2ml / 100L per day. The standard dose is carefully calibrated to work for most environments. This amount has been tested to work well for most tanks.However, if you have a very spar

Best time of the day to dose?

Plants absorb and store nutrients across the day, so dosing timing is not important. Pick a schedule that is easy to follow. Consistency over the longer time horizon matters. Most tanks in the 2hr gallery are dosed at the end of the day.

Dosing Frequency

Low-light tank without CO2 injection?Dosing once per week is fine. Fast-growing plants under strong lighting?It is better to dose daily or at least 4 times a week. This provides a more consistent level of nutrition in the tank, which matters for fast

How soon should I start dosing?

Immediately upon planting! :). Freshly planted aquatic plants do not have established root systems, and have limited ability to draw on substrate nutrients until their root zones develop. However, they can draw in water column nutrients through their

Can I dose APT 1, APT3 and/or APTe together?

A common question is whether it is OK to 'mix and match' APT 1, APT 3 and/or APT e together. Yes you can do that. For example, after adding more fish, you can switch from using solely APT 3 to 'half and half' across APT 1 and APT 3. Using half APT 1

Using APT with an auto doser

APT can be used with auto-dosers- many people do so. However, as APT is highly concentrated, crystallization can occur upon evaporation. You can dilute APT with distilled water 1:1 (and double the dosage) to reduce possible crystallization. When dilu

Can I do less water changes?

The main purpose of water changes is not to dilute nutrient levels in the aquarium but to remove excess dissolved and solid organic waste. In tanks with higher light levels, organic waste is the prime trigger for algae, and large regular water change

Should I add more Iron?

The iron content in the APT formula is sufficient. In tanks using APT, excess iron remaining in the water column can be easily detected by accurate iron test kits. Iron only helps to maintain pigmentation. Contrary to popular belief, excess iron does

Problems after switching to APT?

A mature tank can respond to better nutrition in several ways. The most common outcome is healthier NEW GROWTH. Old leaves do not rejuvenate even when conditions improve, and may even deteriorate faster, as we explain here. Old growth needs to be rem

Why are my nitrate / phosphate readings low?

When we measure the water for nitrates, the reading is the residual level after plant absorption. Plants do not need a constant excess of nitrogen to grow well. Even in tanks with fish, it is actually normal and healthy to have zero NO3 readings- it

Can I use APT SKY with APT fertilisers?

Yes you definitely can 😀. The amount of trace minerals in APT SKY is very small- only to replenish the minerals in RO/ RODI water to the levels found in soft tap water. APT SKY is designed to be used together with APT fertilisers. Rotala florida gro

Will activated Carbon affect fertilizer usage?

Activated carbon is effective at removing larger organic molecules and less effective at remove simple dissolved ions. Here is a table that gives you a good idea of what is removed by carbon.High to moderate adsorption of:Arsenic, Bleach, Chlorine, C

Will a UV lamp / UV steriliser affect APT?

UV does break down iron chelates over time. However, relative to the amount of iron in our fertilisers, the overall impact is minimal and does not affect the efficacy of the product. It is perfectly fine to use APT with the UV lamps / UV sterilisers.