Hydroponic growing systems are a great way for individuals to grow their own vegetables and produce out of their homes for relatively cheap. While this hard work will typically go off without a hitch for most people who build their own hydroponics system, some growers may encounter a few setbacks such as pests or even diseases occurring in their plants. Let’s break down a few of these, and what you can do to combat these pests and problems from overtaking your hard-grown produce.

Spider Mites

Spider mites are among the most common pests you’ll need to deal with when running a hydroponic system. These mites are less than a millimeter in size and are arachnids that can do serious damage to your plants. The most common way to spot spider mites is to either check for spider webbing or to take a tissue and wipe at the bottom of your plant’s leaves. If there are small streaks of blood, it’s likely you have spider mites. Creating a mix of water and alcohol can be used in a spray bottle to kill these mites.


Thrips are smaller, parasite-like insects roughly five millimeters long. Though difficult to identify at first, they have tell-tale signs of an infestation. Look for black specks on top of leaves, or for sections of your leaves that are turning brown and dry. Your leaves may also be spotted and yellow. This occurs from the thrips sucking the nutrients from your leaves. Pruning your plants regularly can help get rid of thrips, as well as using insecticidal soaps or neem oil.


Aphids, also sometimes referred to as plant lice are small insects of a variety of colors (green, black, gray.) Aphids quickly become large-scale infestations due to the fact they reproduce quickly. Additionally, they weaken and kill plants but sucking the juice from the leaves and stems. They may appear anywhere on the plant, but typically they’ll gather near the bottom at the stems. Thankfully, there are several ways to get rid of Aphids such as sticky traps, knocking them into the water and drowning them, or using organic oils such as neem or essential oils to get rid of them.


Another tiny pest at one millimeter long, these flies appear as small, white moths. While they can be easy to spot since they have a familiar appearance, they can quickly become difficult to kill as they can easily fly away and avoid most methods of removal. They will cause white spots and yellowing in plants which can ultimately kill them. Consider utilizing hanging sticky traps in order to capture whiteflies and rid yourself of them.

Fungus Gnats

Fungus gnats are an interesting pest. While they won’t harm your plants as adults, their larvae will feed on roots which can stunt the growth of your plant and possibly cause bacterial infections which can kill your plants. The best way to kill these gnats is to mix peroxide and water and pour it into the root zone of your plant. Peroxide will kill a fungus gnat larvae on contact, and will likely kill adults as well.

Powdery Mildew

If it looks like someone has taken your plant and sprinkled a white powder all over your leaves and stems, it’s likely your plant has come down with powdery mildew. If left untreated, this will stunt your plant’s growth, cause drooping and wilting leaves, as well as the yellowing of the stems and plant tissue. If left untreated for long periods of time, powdery mildew will kill your plants. If you notice PW buildup on your plant, wipe it clean with a sanitized Lysol wipe and spray your plant with water as well.

Gray Mold

The cousin of the deadly black mold, gray mold is sometimes referred to as a ‘ghost spot.’ This is due to the gray spots and abrasions which will begin appearing on leaves and plant tissue when the mold first becomes present. If gray mold is left untreated, it will cause full-scale plant rot and death, turning the stems and matter brown. To get rid of gray mold, utilize peroxide or rubbing alcohol with water and sprits and wipe away the infection. You may need to prune leaves or amputate limbs from your plant if the gray mold has become serious enough.