Introduction: How to Mix Hydroponic Liquid Nutrient Solution

Having the right nutrient solution is critical for your hydroponic system as it's the sole source of nutrient. While the importance of the solution can't be understated, it's also very easy to mix and test your solution these days.

Just follow these basic steps and you'll have your nutrient solution all set.
See why pH is important to manage at Captain Hydroponics or just check out the latest hydroponic tip.

Step 1: Test Your Local Water

• Fill the vial half way with tap water.
• Squirt 5 drops of pH indicator into the vial and tap the side.

My water is probably about 8.0. This is very common in the US.

Step 2: Mix Your Nutrient Solution

Fill the container you wish to store your solution in. I'm just mixing a 1/2 gallon jug today for this demonstration.
Add the liquid nutrient additive to the water according to the directions. I'm only using FloraDuo A (and not B) as I'm looking to spray this on some seedlings. General Hydroponics recommends 3 tsp. per gallon so I added 1.5 tsp to my container.

It's hard to tell in the picture but my water turned a very slight shade of yellow.

Step 3: Test the PH of Your Nutrient Solution

Now you need to retest the pH of your water. You should expect the pH to drop a little when you add your liquid fertilizer but it probably won't be enough as my water was at least 8.0.

Make sure you wait at least 15 minutes after the last step before testing so the nutrients are evenly distributed.

• Using the supplied siphon, I removed ½ a vial worth of solution for testing.
• Squirt 5 drops of pH indicator into the vial and tap the side.

As you see below my pH is still a bit high.

Step 4: Adjust PH

Use the siphon and add 0.5ml of pH down. You want to go slow so you don't over shoot your pH target. GH's website recommends going in 1ml of adjuster increments per gallon of water.

After adding the pH adjuster, shake or stir your water and wait five minutes.

Step 5: Retest the PH of Your Nutrient Solution

Again fill up the test tube 1/2 way for testing.
Squirt 5 drops of pH indicator into the vial and tap the side.

As you can see in the picture below.... Success! If it was still green, I'd repeat step 4.

So that's all you have to do. You can follow this exactly or scale it to your needs.

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