pH Up and pH Down by Growth Technology bottles side by side, matched pH adjuster pair

pH Up & Down Set by Growth Technology — Matched pH Adjuster Pair, 250ml or 1L

GT-PH-SET-250ML

$31.90 $29.95 Save $1.95
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Growth Technology pH Up and pH Down together, in matching 250ml or 1L bottles. Everything you need to bring a nutrient solution into range.

Size
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Pairs well with

Sooner or later every hydroponic grower overshoots the pH in one direction and needs to come back the other way. This set puts both of Growth Technology's adjusters on the shelf together: pH Up (potassium hydroxide 480 g/L) to raise a solution, and pH Down (phosphoric acid 85% w/v) to lower it, in matching 250ml or 1L bottles for less than buying them one at a time. Both are dosed with a dropper after the nutrient is mixed, using Growth Technology's test, add, stir, retest method, with a target of 5.5–6.5 for their hydroponic and coco nutrients. Both are Schedule 6 poisons and Class 8 corrosives, so gloves and eye protection come with the territory.

Dangerous goods: road freight or pickup. Both bottles are Class 8 corrosives and can't travel by standard post. Online orders go by dangerous-goods road courier at a separate freight charge that isn't included in free shipping over $499*, and delivery may take longer. We'll contact you after you order to confirm. Prefer to skip the freight? Choose pickup from our Invermay store or local delivery at checkout.
What's in the set 250ml Pair
pH Up 250ml — raises pH$15.95
pH Down 250ml — lowers pH$15.95
Bought separately$31.90
250ml Pair — you save $1.95$29.95
1L Pair
pH Up 1L — raises pH$35.95
pH Down 1L — lowers pH$39.95
Bought separately$75.90
1L Pair — you save $3.95$71.95
Both directions coveredOvershoot on the way down and pH Up brings it back. Fresh mix sitting high and pH Down sorts it. One order, no waiting on the second bottle.
Cheaper than two singlesThe 250ml pair saves $1.95 and the 1L pair $3.95 on the single-bottle prices.
Matching sizesTwo 250ml bottles for a tent or a few reservoirs, two 1L bottles for bigger systems. One size choice, both bottles.
Built for GT nutrientsGrowth Technology's Ionic and GT Coco directions both finish with a test and adjust to pH 5.5–6.5. These are the same maker's tools for that step.
Nutrients, not fillerspH Up leaves potassium in the tank and pH Down leaves phosphate, both minerals plants use.
Same bottles as the singlesEach set is the standard pH Up and pH Down bottles, not a different formula.
Read before you buy Poison S6, both bottles. pH Up is potassium hydroxide 480 g/L (UN 1814) and pH Down is phosphoric acid 85% w/v (UN 1805); both are Class 8 corrosive dangerous goods. Growth Technology warns pH Up may cause severe burns and attacks skin and eyes. Wear protective gloves and eye and face protection, keep both bottles in a secure, well-ventilated place out of reach of children, and never pour one into the other. First aid: contact the Poisons Information Centre on 13 11 26 or a doctor at once. If swallowed, do not induce vomiting; give a glass of water. Eyes: hold the lids apart and flush with running water for at least 15 minutes, then see a doctor. Skin or hair: remove contaminated clothing and flush with running water.

Specifications
Brand: Growth Technology
Type: pH adjuster pair
In the 250ml Pair: pH Up 250ml and pH Down 250ml
In the 1L Pair: pH Up 1L and pH Down 1L
pH Up contains (label): Potassium hydroxide 480 g/L
pH Down contains (label): Phosphoric acid 85% w/v
Dose: No fixed rate: add drop by drop, test, repeat
Target pH: 5.5–6.5 for Growth Technology hydroponic and coco nutrients
When to adjust: Last, after nutrients and additives are mixed and settled
Poisons schedule: S6, both bottles
Dangerous goods: Class 8 corrosive: UN 1814 (pH Up), UN 1805 (pH Down)
Protective equipment: Gloves, eye and face protection
Storage: Secure, well-ventilated place, out of reach of children
Delivery: Dangerous-goods road courier at a separate freight charge, store pickup or local delivery

Grower's Tip
  • Calibrate your pH pen first. Both bottles are only as good as the reading you are chasing.
  • Adjust last, after the nutrient and additives are mixed and settled.
  • One drop at a time, stir, retest. Both are concentrated and overshoot fast.
  • Keep a separate dropper for each bottle and label them. Never pour one into the other.
  • Write down drops per litre for each mix. After a couple of rounds you will know your starting dose.
  • Store both locked away and capped. They are Schedule 6 poisons and corrosives.

How To Use It
1Mix your nutrients and any additives into the reservoir, stir well and let the solution settle.
2Test the pH with a calibrated pen or meter.
3Put on gloves and eye protection. If the reading is too low, add pH Up with its own dropper; if it is too high, add pH Down with its own dropper. Count the drops and stir.
4Retest. Repeat until the solution reaches your target pH, which is 5.5–6.5 for Growth Technology's hydroponic and coco nutrients.
5Write down which bottle and how many drops per litre it took, for next time.

Pairs Well With

Frequently Asked Questions
What's in the pH Up & Down Set?

One pH Up and one pH Down from Growth Technology, both 250ml in the 250ml Pair or both 1L in the 1L Pair.

Is it cheaper than buying them separately?

Yes. The 250ml Pair is $29.95 against $31.90 for two singles, and the 1L Pair is $71.95 against $75.90.

Are these dangerous?

Yes. Both are Schedule 6 poisons and Class 8 corrosives. Wear gloves and eye and face protection every time, and keep them locked away.

How much do I use?

There is no fixed rate. Add a small amount with a dropper, counting the drops, stir, retest and repeat until you hit your target, then record the drops per litre.

What pH should I aim for?

5.5–6.5 for Growth Technology's hydroponic and coco nutrients.

Can you post the set to me?

Not by standard post. Both bottles are dangerous goods, so online orders go by dangerous-goods road courier at a separate freight charge, not included in free shipping over $499*. We contact you after you order to confirm. Pickup from our Invermay store and local delivery are also available.

Can I buy different sizes, like a 1L pH Down and a 250ml pH Up?

Not as a set. Buy the singles separately in whatever sizes you want.

What do I do if either gets on my skin or in my eyes?

Skin: remove contaminated clothing and flush with running water. Eyes: hold the lids apart and flush with running water for at least 15 minutes, then see a doctor. For anything more, call the Poisons Information Centre on 13 11 26.

Select Size

Both directions, one order

Corrosive, so it travels by dangerous-goods road freight or pickup in Invermay. We'll call to confirm online orders.

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Order by 2pm and it ships the same business day from Invermay, Tasmania.

Calculated at checkout by weight and destination. Free shipping over $499*.

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