APT SKY FAQ

I'm new to planted tanks. Do I really need SKY?

If you are using reverse-osmosis (RO / RODI) water, it is important to replenish the minerals removed as part of the RO process. APT SKY is simply the best remineraliser. It is powerful (and therefore economical), uniquely comprehensive, and does not negatively alter macro nutrients, KH and pH.

If you are not using an RO/ RODI system because you are lucky enough to have stable softwater, and have a nature-style aquarium ( a mix of plants, hardscape and fish), APT SKY expands your playground to popular species like Rotala macrandra which require higher levels of magnesium than what is commonly found in softwater regions.

If you are not using an RO/ RODI system because you are lucky enough to have stable softwater, and plan to keep shrimps, APT SKY is a great booster for shrimp health and reproduction, due to the Calcium and other minerals it provides. Note: Shrimps are bred in varying water parameters. Always try match the shrimp's 'home' parameters (i.e the farm or place where they were bred).

How can I calculate how much to dose?

Each 3.5g / 5ml ( 1 scoop) adds 12ppm Calcium and 3.5ppm Magnesium and raises GH by 2.5 dGH in 60L of water.

We recommend a target of 5-7 dGH. Use the SKY Dosing Calculator above.

Is there a target or recommended TDS?

Unfortunately, no.
This is because TDS readings can vary considerably. A high reading is not necessarily good, and a low reading is not always insufficient. For example, 100pm of Calcium in water (high TDS) is relatively harmless while 5ppm of copper (low TDS) will kill most aquatic life.

TDS, or "Total Dissolved Solids" simply measures all dissolved organic & inorganic substances in the water. However, it does not tell us WHAT is in the water. What makes up the TDS value is alot more important than the aggregate reading.

Then why do people measure TDS?

TDS is very useful as a relative test.

It is like a thermometer.
It is useful to check if it rises or falls over time, as the cause may be consequential.

If your room temperature rises sharply, may be a sign of a breakdown in ventilation or clogged air conditioning. It may came from the window being left closed or open. It may result from the automatic blinds failing to work. It may be because of an overheated computer in the room.

As a relative test, TDS is useful when adding new hardscape or other materials to the tank. If TDS rises over time, it means that some part of the rock is dissolving. Totally inert rock will not change the TDS value.

Read more about TDS here.

How do I know if I'm growing 'conflicting' species?

We cover many popular plants on our website, so this is a good place to start. APT SKY removes the need for guesswork. If you have low KH to start with, APT SKY optimizes water parameters for both softwater and hardwater plants. If you have hardwater (above 2dKH), an RO/RODI system makes plant growing alot easier as the majority of tropical aquatic plants prefer softer water.

I'm new to planted tanks. Should I start with a fertiliser, or APT SKY?

They do different things. It is always important to fit plants to their preferred water parameters. It is much harder to grow Rotala macrandra in hardwater for example. They won't die, but will struggle to display good form or coloration. Better nutrition in the form of fertilisers cannot compensate for mismatched water parameters.

How do I add SKY to my tank?

A good way is to add it first to a small container, shake to dissolve it partially, and then to pour the solution into the tank.

You may also add it directly, in powder form, into the tank if you have good water flow.

In zones of poor flow, it may take more than a day for it to dissolve completely.

I don’t use RO water. How much should I dose?

If you have water that is considered 'soft' (you don’t experience much mineral residue in your kettle etc.),

you can follow the standard dose:

15ml per 60L.

Dosing above the 36ppm Ca / 10ppm Mg does not have negative effects.

If you want to be precise, get a copy of your local water report, which will tell the amount of Calcium and Magnesium in your tap water, usually in mg/L which is equivalent to ppm (parts per million). Or get a GH test kit and measure the GH of your tank's water.

USING YOUR WATER REPORT

Let’s say your tap water has 12ppm of Calcium and 3ppm of Magnesium (and you have a 60L tank).

Each 5ml adds 12ppm Ca and 3.5ppm Mg.

So to reach the target of 10ppm Mg, you need to add 10ml (2x3.5ppm = 7ppm).

When added to the existing 3ppm, that gives 10ppm.

Calcium will be raised by 12x2= 24ppm.

When added to your existing 18ppm of Calcium, you get 24ppm= 18ppm = 42ppm of Calcium.

This is higher than the targeted 36ppm, but that is OK.

USING YOUR GH TEST KIT

Let's say your tank water measures 2 dGH. You can use the APT SKY Dosing Guide above to find out how much you should dose based on the water volume. When dosing the first time, use your tank volume as the Water Volume. Subsequently, the Water Volume is the amount of water changed.

Really? Dose per water changed?

If we dose according to the water replaced during water change, wouldn't the overall average GH / Calcium / Magnesium levels drop over time?

Yes, technically the 'residual' water that was not changed would have a lower level of Calcium and Magnesium after being absorbed by plants.

You can indeed measure the GH of your total tank water after every water change, and then add APT SKY to hit the targeted ~7 dGH level.

However we find the difference to be negligible in terms of actual impact to plant health.

I have hardwater. How should I use APT Sky?

It depends.

Hardwater simply means your water has high mineral content.

This can mean either:

(a) a high level of carbonates (positive KH reading) or

(b) a high level of Calcium / Magnesium (positive GH reading) or

It is common for "hardwater" to have both high GH and KH because sources of hardwater usually come from areas with limestone [CaCO3] - which contributes to both GH [Ca ion] and KH [CO3 ion]. However, hardwater can be high in GH and low in KH and vice versa.

Basically, if you have GH below 7 dGH, you can use APT SKY to raise GH to the recommended ~7 dGH zone.

However APT SKY does not alter KH, so simply raising GH to the ~7dGH zone will not allow you to keep softwater plants.

Read more about softwater and hardwater here.

To understand more about your water's suitability for various plants, perform these 2 steps:

Step 1:

Get a copy of your local water report, and /or a KH test Kit.

Most livestock and plants are more forgiving to high GH than to high KH.

If you have KH above 3 dKH, it means that it is harder to keep plants that prefer softwater (generally, most tropical aquatic plants prefer softwater).

You can simply focus on plants that take hardwater well.

APT SKY cannot change or lower KH.

Step 2: Consider a Reverse-Osmosis (RO) system.

If you want to grow softwater plants, using RO water makes it much easier.

If you are using RO water, then simply dose 15ml per 60L of RO water.

I have high KH but low GH. How should I use APT Sky?

You can still use APY SKY to raise GH to the targeted ~7 dGH zone.

However, do note that if you have KH above 3 dKH, it means that it is harder to keep plants that prefer softwater (generally, most tropical aquatic plants prefer softwater).

You can simply focus on plants that take hardwater well.

APT SKY cannot change or lower KH.

Consider a Reverse-Osmosis (RO) system.

If you want to grow softwater plants, using RO water makes it much easier.

If you are using RO water, then simply dose 15ml per 60L of RO water.

My tap / tank water has a +ve GH reading. How much APT SKY should I dose?

GH measures the total amount of Ca/Mg ions in the water (and other divalent cations).

Calcium is present in most tap water. However, magnesium is often over-looked.

If your tap water measures, say 3 dGH, it is possible that all of it is made out of Calcium ions, and no magnesium is present.

In this case, magnesium still has to be dosed.

You can follow the APT SKY Dosing Guide to raise your GH to the targeted ~7dGH zone.

I have a GH Test Kit and it reads 5 dGH. Should I dose APT Sky?

No.