Algae is that mossy, slimy gunk you see gathering on ponds in summer. Unfortunately, algae gets in a ton of other places too. That includes your hydroponic system. It might look green, reddish black, or even brown, but it definitely looks like slimy plant-like growth. You might even notice an odor if there’s a lot of algae. 

Algae usually accumulates in the hydroponic reservoir, but you might also find it on other pieces of equipment. Because of this, algae can block equipment and clog up your system.

A little algae isn’t a big problem. However, if algae starts taking over your hydroponic system, your plants will suffer. Algae quickly reaches mass amounts, and it can grow back very quickly. 

There’s a bigger problem with algae than just messing with your hydroponic equipment. It ‘competes’ with your plants’ roots for oxygen and other vital nutrients. Not only that, algae provides a food source for pathogenic fungi. If that happens, you have even bigger problems to worry about. As algae begins to die and break down, it can release chemicals and throw your system out of balance. 

Algae affects Hydroponics

How to get rid of algae in hydroponic system

Prevention is the best medicine, especially when it comes to algae in your hydroponic system. Keeping a lid on your hydroponic reservoir will help inhibit algae growth. Try to limit the amount of light that reaches your nutrient solution. If you can, eliminate light exposure entirely. If you have plant holes in your system, take care. The holes shouldn’t be larger than absolutely necessary to hold your plants. If you have open plant holes you aren’t using, cover them up. 

Prevent algae from a previous crop getting into a new crop with a thorough cleaning. Of course, you should always give your system a good clean before a new crop, but it prevents algae too. 

If you’re too late for prevention, you can still fix algae problems in your hydroponic system. Start by eliminating any light leaks reaching your nutrient solution. Make sure you filter and scrub out as much algae as possible. If the problem is really out of control, you can choose to use an algaecide. Be careful if you use these, though. Measure the dose very carefully, and exactly as the directions indicate. 

Algaecide can get rid of algae, but it can also damage plants with sensitive root systems. Young plants can also sustain damage from algaecides. 

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