This article is being printed in a hydroponics magazine in September.....yes I am the author. The brand of dye is called aquashadow lc in canada, made by Applied Biochemists in the U.S. It is safe for humans, fish and plants.
Algae is an often misdiagnosed infection and once acquired, can kill your garden within a week. Many growers will have a perfect set-up with system water below 21°C, plenty of air flow and plenty of water aeration, and yet they are unable to grow so much as a dandelion. Often misdiagnosed as pythium, algae can be introduced into your hydroponic system through a handful of ways; and if acquired, it will multiply rapidly and destroy a crop.
My Story
After 10 years of relatively trouble-free hydroponic gardening I started having problems. The only thing that changed was the amount of lumens I was growing with. I went from a 400 watt to 1000 watt lighting system as I was told this was the key to maximum yields. Slime developed on all surfaces that came into contact with water; the air stones I was using seemed to be coated the worst. Even though I was using chillers and had all of my air stones replaced, the roots turned brown and my plants died. Furthermore, the plant was small with a root mass no bigger than a fist. I drained and cleaned the system and circulated a mixture of half bleach, half water for a day, replanted and crossed my fingers that the pythium would not return. However, I would not be so lucky. It did return, again and again. The hydrogen peroxide I was using did me no good. I brought a sample of the slime to a hydroponics store and was told it was not pythium, although they were unsure what else it could be.
The next six months were the most frustrating for me and my garden. The plants did fine under fluorescents but when transferred to the 1000 watt room, they wilted and eventually died. Once again, my wife and I took our problem to an indoor gardening retail shop and explained the conditions we were experiencing. The consultant told her it sounded like low light algae and sold her a bottle of algae and sludge reducer. It worked immediately and I was able to grow trouble free. That is until I increased my lumens once again by reducing the distance between my lights by 30 cm.
My system was infected almost immediately and the algae reducer worked for a short term. I was able to grow plants but the water had to be changed at least once a day. By luck I was talking to a gentleman at a commercial gardening supply store and he suggested I use a dye for the water that is developed to reflect sunlight. I have not looked back since.
Signs of Infection
The signs of an infected system are a light, white slime coating on the inside of the buckets or the sides of the reservoir. The new growth will be curled over like a ram's horns and the whole plant will look wilted. When the infection is in the early stages, a slippery coating can be felt. Keep in mind, even a mild infection will still destroy your plants. If the infection is severe enough, your air stones will be covered fairly thick with a light brown slime and every surface exposed to the water will feel slippery. The roots will stop growing, turn brown and die. This can happen, even when youve taken the utmost precautions with your systems settings.
Causes of Algae
1. High lumen light intensity
The main cause of algae in a hydroponic grow system is light coming into contact with water. This only happens after a certain amount of lumens are utilized, which explains why you can grow with uncovered, untreated water under fluorescents and not HIDs.
2. Top watering
Another way to infect your system is through top watering your growing medium. While fluorescent light cannot infect water it can cause algae build-up on your growing medium during the cloning phase. If you top water infected medium you are introducing algae into your system. If exposed to high intensity light your nutrients can become infected. The nutrients will turn cloudy and if used will cause plants to wilt within a day. Any water contacted by HIDs then introduced into your system will become contaminated.
Reverse osmosis systems will not prevent algae and neither will water purifiers. Algae is not introduced into your system externally; it is caused within a system, directly or indirectly by HIDs. Hydrogen peroxide will not control an infection nor will bleach. Hydrogen peroxide is mainly used for fighting pythium; by itself it's ineffective, even at high doses, on algae.
Solutions
Before adding the selected products to your nutrient solution you have to make sure there is absolutely no light contacting the water. The lumens produced by HIDs can penetrate thin plastic so either double up everything or use thick sheeting to cover any areas that light might penetrate. Gravel or rocks on top of your medium can also allow enough light in to cause problems, so make sure to cover your medium with sheeting thoroughly. Make sure your nutrient solutions are stored away from any HID light; if your nutrients turn cloudy, discard them. Any stored water that comes into contact with HIDs should not be introduced into your system. I have had a one foot long section of drain line being used for a breather, and even then, the lumens directed down into it was enough to cause an infection. Once I capped it, the system returned to normal.
Tips and Products
Fungus gnats are almost always present at the same time as algae, leading many to believe these pests are solely to blame for their wilting plants. However, they are most likely secondary to the algae. After all, if there's food they will come. Only after you get rid of what they eat will they disappear.
MM2000 and Sticky Strips
The first two products to utilize are an organic-based foliar and root application along with sticky strips. The foliar spray is a fungicide with pyrethrum mixed in. It seems to work great along with sticky strips for the fungus gnats and is used at the labelled dose, which is added directly to the reservoir. It will give your water a lemon smell and can be used full time as a precaution if desired.
A mixture of three per cent hydrogen peroxide at a rate of five millilitres per litre also works great for the system. This is almost double the maximum recommended dosage of three millilitres per litre but it has been used successfully with no undesired effects. H2O2 is used for the cleansing effect it has on the entire system, including roots, with an added benefit of oxygenation of the water.
Algae and Sludge Reducer
This product is used to destroy algae already infecting a system and as a preventative measure whenever top watering your medium; it can also be added to the reservoir with every water change. This product is found anywhere pond supplies are sold and is usually part three in a three part pond care package. It can be used at a rate of one millilitre per litre safely.
Pond Dye
Pond dye is the last key to the puzzle; the golf courses use this to in their ponds to ensure algae doesn't overtake them. It is made to naturally reflect the suns rays and works great for the control and prevention of algae. A very small amount goes a long way; a four litre jug will dye over 300,000 litres of water although I strengthen it to ½ ml to every litre for hydroponics. I recommend you purchase the variety that is safe for fish as well as plants.
The water in my system is city water, taken from a garden hose and poured directly into the reservoir. I used no pre-treatment at all. A friend of mine has gone the pre-treatment route with no success; she is currently growing in dirt after giving up on hydroponics due to algae. I informed her of my findings but she is unable to switch back yet due to the money she spent on pre-treatment. How many once hydroponic growers are now growing in dirt because they didnt have the correct information to diagnose their problem? As far as I am concerned I just got lucky. Remember the algae is coming directly or indirectly from your lighting. If your problems are mineral related you will have to pre-treat your water, but make sure that is the case as pre-treatment can be expensive.
The combination of these five products together, along with a system that is secure from intruding light, will ensure algae will not be a threat to your valuable garden.
Happy growing.
Algae is an often misdiagnosed infection and once acquired, can kill your garden within a week. Many growers will have a perfect set-up with system water below 21°C, plenty of air flow and plenty of water aeration, and yet they are unable to grow so much as a dandelion. Often misdiagnosed as pythium, algae can be introduced into your hydroponic system through a handful of ways; and if acquired, it will multiply rapidly and destroy a crop.
My Story
After 10 years of relatively trouble-free hydroponic gardening I started having problems. The only thing that changed was the amount of lumens I was growing with. I went from a 400 watt to 1000 watt lighting system as I was told this was the key to maximum yields. Slime developed on all surfaces that came into contact with water; the air stones I was using seemed to be coated the worst. Even though I was using chillers and had all of my air stones replaced, the roots turned brown and my plants died. Furthermore, the plant was small with a root mass no bigger than a fist. I drained and cleaned the system and circulated a mixture of half bleach, half water for a day, replanted and crossed my fingers that the pythium would not return. However, I would not be so lucky. It did return, again and again. The hydrogen peroxide I was using did me no good. I brought a sample of the slime to a hydroponics store and was told it was not pythium, although they were unsure what else it could be.
The next six months were the most frustrating for me and my garden. The plants did fine under fluorescents but when transferred to the 1000 watt room, they wilted and eventually died. Once again, my wife and I took our problem to an indoor gardening retail shop and explained the conditions we were experiencing. The consultant told her it sounded like low light algae and sold her a bottle of algae and sludge reducer. It worked immediately and I was able to grow trouble free. That is until I increased my lumens once again by reducing the distance between my lights by 30 cm.
My system was infected almost immediately and the algae reducer worked for a short term. I was able to grow plants but the water had to be changed at least once a day. By luck I was talking to a gentleman at a commercial gardening supply store and he suggested I use a dye for the water that is developed to reflect sunlight. I have not looked back since.
Signs of Infection
The signs of an infected system are a light, white slime coating on the inside of the buckets or the sides of the reservoir. The new growth will be curled over like a ram's horns and the whole plant will look wilted. When the infection is in the early stages, a slippery coating can be felt. Keep in mind, even a mild infection will still destroy your plants. If the infection is severe enough, your air stones will be covered fairly thick with a light brown slime and every surface exposed to the water will feel slippery. The roots will stop growing, turn brown and die. This can happen, even when youve taken the utmost precautions with your systems settings.
Causes of Algae
1. High lumen light intensity
The main cause of algae in a hydroponic grow system is light coming into contact with water. This only happens after a certain amount of lumens are utilized, which explains why you can grow with uncovered, untreated water under fluorescents and not HIDs.
2. Top watering
Another way to infect your system is through top watering your growing medium. While fluorescent light cannot infect water it can cause algae build-up on your growing medium during the cloning phase. If you top water infected medium you are introducing algae into your system. If exposed to high intensity light your nutrients can become infected. The nutrients will turn cloudy and if used will cause plants to wilt within a day. Any water contacted by HIDs then introduced into your system will become contaminated.
Reverse osmosis systems will not prevent algae and neither will water purifiers. Algae is not introduced into your system externally; it is caused within a system, directly or indirectly by HIDs. Hydrogen peroxide will not control an infection nor will bleach. Hydrogen peroxide is mainly used for fighting pythium; by itself it's ineffective, even at high doses, on algae.
Solutions
Before adding the selected products to your nutrient solution you have to make sure there is absolutely no light contacting the water. The lumens produced by HIDs can penetrate thin plastic so either double up everything or use thick sheeting to cover any areas that light might penetrate. Gravel or rocks on top of your medium can also allow enough light in to cause problems, so make sure to cover your medium with sheeting thoroughly. Make sure your nutrient solutions are stored away from any HID light; if your nutrients turn cloudy, discard them. Any stored water that comes into contact with HIDs should not be introduced into your system. I have had a one foot long section of drain line being used for a breather, and even then, the lumens directed down into it was enough to cause an infection. Once I capped it, the system returned to normal.
Tips and Products
Fungus gnats are almost always present at the same time as algae, leading many to believe these pests are solely to blame for their wilting plants. However, they are most likely secondary to the algae. After all, if there's food they will come. Only after you get rid of what they eat will they disappear.
MM2000 and Sticky Strips
The first two products to utilize are an organic-based foliar and root application along with sticky strips. The foliar spray is a fungicide with pyrethrum mixed in. It seems to work great along with sticky strips for the fungus gnats and is used at the labelled dose, which is added directly to the reservoir. It will give your water a lemon smell and can be used full time as a precaution if desired.
A mixture of three per cent hydrogen peroxide at a rate of five millilitres per litre also works great for the system. This is almost double the maximum recommended dosage of three millilitres per litre but it has been used successfully with no undesired effects. H2O2 is used for the cleansing effect it has on the entire system, including roots, with an added benefit of oxygenation of the water.
Algae and Sludge Reducer
This product is used to destroy algae already infecting a system and as a preventative measure whenever top watering your medium; it can also be added to the reservoir with every water change. This product is found anywhere pond supplies are sold and is usually part three in a three part pond care package. It can be used at a rate of one millilitre per litre safely.
Pond Dye
Pond dye is the last key to the puzzle; the golf courses use this to in their ponds to ensure algae doesn't overtake them. It is made to naturally reflect the suns rays and works great for the control and prevention of algae. A very small amount goes a long way; a four litre jug will dye over 300,000 litres of water although I strengthen it to ½ ml to every litre for hydroponics. I recommend you purchase the variety that is safe for fish as well as plants.
The water in my system is city water, taken from a garden hose and poured directly into the reservoir. I used no pre-treatment at all. A friend of mine has gone the pre-treatment route with no success; she is currently growing in dirt after giving up on hydroponics due to algae. I informed her of my findings but she is unable to switch back yet due to the money she spent on pre-treatment. How many once hydroponic growers are now growing in dirt because they didnt have the correct information to diagnose their problem? As far as I am concerned I just got lucky. Remember the algae is coming directly or indirectly from your lighting. If your problems are mineral related you will have to pre-treat your water, but make sure that is the case as pre-treatment can be expensive.
The combination of these five products together, along with a system that is secure from intruding light, will ensure algae will not be a threat to your valuable garden.
Happy growing.
