Measurements Every Hydroponics Grower Should Take
As I’ve learned from my hydroponics grows, making sure you keep good records is extremely important. Not only will this will you save money (since you’ll only replace the nutrients when you need to) but it also could save your plants. By knowing exactly how much nutrients your plants are consuming, what the pH of the water is, etc. you will be able to immediately respond to any changes in the environment that could spell the end of your grow.
I’ve put together a checklist of some common measurements that you could take every day. You should at least try to take the first four. Both pH strips/meters and TDS/EC meters are fairly cheap and are an extremely good investment. Thermometers and humidity sensors are easy to pick up at your local hardware store.
- pH levels – pH plays a very important role in a hydroponic nutrient reservoir. You will want to keep your pH in between 5.5 and 6.5 in order to prevent nutrient lockout, which is when your plant cannot absorb all the nutrients present in the solution, even though they’re all present. You’ll want to use pH strips or a pH meter for this (make sure that the meter is calibrated).
- Total Dissolved Solids (TDS) – This measures the amount of nutrients in your solution. This number should be anywhere from 500 ppm to 1500 ppm, depending on the type of plant and stage of growth. You can also use an EC (electrocondutivity) meter to measure total dissolved solids. To convert from EC to TDS, multiply by 500.
- Temperature – Depending on your plant, temperature could be an important factor to consider. Proper temperatures will keep the plants at their best, and repel disease, fungus, and insects. For most plants temperature should at least be between 65 and 80 degrees Fahrenheit, but each plant has its optimal grow range and will grow best within this range.
- Humidity – Plants like a relative humidity range of 50-80%. Too much humidity prevents plants from breathing and provides the perfect environment for algae and fungus to thrive. Do your plants a favor and keep the air just right.
- Dissolved Oxygen – Dissolved oxygen meters are expensive, but they may be a good investment if you keep losing harvests to root rot. Basically, plants need oxygen too, so if your nutrient solution does not have enough oxygen in it, you are basically drowning your plants. Moreover, plant parasites like Pithium thrive in enrivonments low in Oxygen, and die in its presence. If you find levels are getting too low, try adding an airstone. If you think your plants may already be experiencing the beginning stages of a Pithium infection, add some houshold hydrogen peroxide to add a good dose of Oxygen to the system.
Tips
Here are some tips so that the data you collect is accurate.
- Make sure that the water level is constant – As your plants drink your water, some of it is inevitably lost through evaporation through the plant’s leaves in a process called transpiration. In order to make sure both your TDS and pH readings are comparable from day to day, you’ll want to make sure that the nutrient solution level is always the same. To do this, make a mark in your reservoir indicating the top of the nutrient solution. When the solution falls below this line, simply add plain water into the reservoir to keep the level constant.
- Try to keep temperature constant – pH levels are affected by the temperature, so try as best you can to keep temperature within a few degrees. This might be hard, so if you can’t control it, don’t sweat it, but do keep it in mind.