APT Sky Plus is the close cousin of APT Sky — a remineralizer that restores the calcium, magnesium, trace minerals, and natural seaweed extract that soft or RO water lacks, all without disturbing the nitrogen, phosphorus, and potassium your fertilizer is calibrated around. The difference is in the carbonate side of the equation: where plain Sky leaves KH and pH untouched, Sky Plus also nudges KH up to around 2 dKH and gently buffers pH into the 7.2–7.6 range. That small amount of buffering guards against the sharp pH swings that very soft, aquasoil-driven tanks are prone to.
At Cuboid, the APT range is what we run in our own aquascaping display tanks — products we use ourselves day in and day out, and recommend without hesitation to anyone serious about a planted aquarium.
Sky or Sky Plus? Reach for Sky Plus if you keep livestock that appreciate a little hardness and stability in the water — 2HR recommends it for those keeping "guppies, mollies and snails," and for anyone worried that aquasoil is driving pH too low. Choose plain Sky for tetras and rare softwater plants that want KH kept at rock bottom. Both are shrimp-safe and both leave your fertilizer ratios intact.
The result is a tank where softwater and hardwater plants can share the same water, shrimp get the steady minerals they need to molt and breed, and your pH holds rather than drifting. It still asks for soft or RO water to start — like any remineralizer it adds minerals rather than removing them — but within that range it gives you a more forgiving, better-buffered version of SKY-boosted water. And like the rest of the line, it's designed to work alongside your APT fertilizers.
Dosing Guidelines: Sky Plus is the same super-soluble, non-caking powder as Sky, just a touch milder per scoop. A simple starting point: one 5 ml scoop (about 3.5 g) per 10 gallons raises GH by roughly 3 dGH (about 53 ppm) and lifts KH slightly toward ~2 dKH. Most planted tanks are happiest around 5–7 dGH (90–125 ppm), so scale to your tank and top up at each water change. For an exact amount matched to your water, 2HR Aquarist's free online APT Sky Plus dosing calculator does the math for you.
Inventory Accuracy
If this item is at low stock, or you are ordering all or almost all of our current inventory, there may be an inventory discrepency. We will contact you about any issues as soon as possible.
Order Processing
Please allow 24 to
48 hrs to process your order. Expect an
email within 48 hrs to let you know your order is on your way.
Store Pickup
If you choose “Pickup
in Store” at checkout, an email will be sent when your order is ready for
pickup. Orders can be picked up during
store hours, see our home page for our current hours. The pick up address is 6637 Easton Rd,
Pipersville, PA 18947
Domestic Shipping Rates
Shipping charges, if
any, for your order will be calculated and displayed at checkout.
