Green Algae Problems

by Jerel Wenger
(West Park, NY)

We have a hydroponic system with a really bad algae problem. Algae is clinging to the roots. Even after cleaning and changing the water, it just grows back the next day. Please help!

Answer: Jerel- algae grows whenever three things are present....water, nutrients, and light. In order to stop the algae, you need to take away one of these three ingredients. Since your hydroponic system is designed to carry water and nutrients all the time, the only option is to eliminate light from coming in contact with the nutrient solution wherever possible.

Start with the nutrient reservoir....make sure you have a nice dark one. Make sure to use a lid on your nutrient reservoir (cut holes just big enough for hoses and cords if you have to). Next, make sure the hydroponic system itself is not letting in a bunch of light. If it is, wrap in in black plastic or aluminum foil. Make sure your plants fit tightly into your system and do not allow light to get in.

If you are using a drip system, cover the surface of your growing medium with black plastic and run your drip emitter underneath the plastic. Otherwise, cut a small hole in the surface of the plastic to minimize the area exposed to light. Be equally protective of the nutrient solution on its way back to the reservoir.

It will take a little while for the algae that is already established to die back. While it is dying back, the dead algae may attract fungus gnats. You could use a weak hydrogen peroxide solution in the nutrient reservoir, but you want to make extra sure you follow the directions for mixing the solution for using with live plants! The peroxide will help clear out the algae and also prevent fungus gnats and other diseases.

Otherwise just let the algae die back naturally, and do an extra water change if the solution gets too funky. Once it is established, sometimes it does not want to leave. Hopefully it will not cause too many other problems! Good luck!

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Feb 28, 2010
by: EzeSpiderweb

I have been studying and learning how to set up my Hydroponic system.. I found U ... I got it my friends... Thank YOU so Much .. I have placed you on my FaceBook and Google

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Hi everyone, Jason from Jason's Indoor Guide here. When I got started with hydroponic gardening more than 24 years ago, my first garden used rockwool cubes and B.C. Nutrients....and I remember thinking to myself yeah, sure, there may be a lot of advantages to gardening with hydroponics, for example there are very few pest problems, therefore very little pest control, no weeding, no plowing or tilling the soil, no soil testing or having to add things into the garden soil, no watering the garden....but for someone who just wants to grow their own vegetables and have more control over their food supply and the quality of the food that they eat, the cost of constantly having to buy grow media and hydroponic nutrients makes this an expensive hobby for most people...

Epic Nutrient Change

I suppose when you take into consideration how much money you save NOT having to buy food at the grocery store, it is surely cheaper to grow your own food hydroponically even with the cost of high quality nutrients. Nevertheless, I didn't have a whole lot of money to work with and I needed to make my efforts as affordable and effective as possible....and in the last 24 years I HAVE learned a thing or two!

As you browse through Jason's Indoor Guide, you will notice all of the systems that I use personally are homemade systems. As I got 3 or 4 years of experience under my belt, I quickly adopted a preference to standing water systems and systems that use expanded clay pellets or lava rock, because the media is re-usable and it eliminates a huge operating expense. So once a hydroponic system is built, garden maintenance is minimal- check and adjust the nutrient solution daily, and to change it completely every 2 weeks....and the biggest operating cost is the hydroponic nutrients. (and the electric bill, lol)...

Homemade Cloner

And, regarding the cost of the nutrients....I experimented for about 3 years with making different compost teas and nutrient teas, but there is still a lot of expense $$$ associated with making high quality nutrient kelp meal, liquid seaweed, rock dust, bat guano, un-Sulfured molasses, worm castings. You can eliminate a lot of this expense by becoming an expert at making high-quality colloidal humus compost, and use your properly made compost as the basis of your hydroponic nutrient solution.

Unfortunately, I have been gardening for over 24 years and I have only just recently mastered this difficult skill....and even then, only because I happened to find a very easy to follow, high quality technique and decided to follow the instructions to the letter. I produced more high quality compost in just one week than I was able to use in a whole year! If you can master the technique, I highly recommend it. It is one of the top 3 things you can do to increase the productivity of your food production efforts, while at the same time decreasing the amount of effort required to grow all of your own food, and decreasing the total cost of operating your food production system.

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The ultimate solution to eliminate the cost of your hydroponic nutrients: Imagine a hydroponic system that does not require you to buy any nutrients, does not require you to make your own compost, and does not require you to brew your own nutrient tea. Seriously! No cost and no effort as far as providing nutrients to your plants! Plus, at the end of the gardening cycle you harvest all of your garden vegetables, PLUS YOU HARVEST FISH from the system--->


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This solution is aquaponics. If you are serious about producing all of your own food and being self-sufficient, this is the ultimate solution for reducing expenses (as much as possible), reducing the total amount of work required, and maximizing the productivity of your gardening efforts. I have been gardening for over 24 years, and it is the perfect food production solution in my opinion.

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Besides mastering how to make high quality compost, learning aquaponics is one of the top 3 things you can do to increase your garden productivity, reduce your total costs, and reduce your total work. The product that I learned from is called Aquaponics4you. With all of my hydroponic gardening experience, the first time I came across the Aquaponics4you product I knew immediately that it was something very special! Place an aquaponics system outdoors and use the sun instead of grow lights, and you have reduced every garden expense to nearly ZERO!

The Same System/ 10 Weeks Later!

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