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For all of my water gardening enthusiasts out there, what is the one challenge we have every spring with our ponds? Algae Bloom!
What Is Algae Bloom?
Although it is a natural phenomenon, algae bloom occurs when there is a rapid increase or accumulation of algae in a water system. The primary cause of algae bloom is a high nutrient level in the pond water. Several factors can contribute to this spike in nutrients.
- Uneaten fish food remaining in your pond water.
- Overfeeding fish can produce excess fish waste.
- Decaying organic material remaining in the pond.
- Lack of aquatic plants.
- Full sun.
- Fertilizer (either from runoff or aquatic plant fertilizer).
Minimizing the Algae Bloom Cycle
There are several steps that you can take to minimize the nutrient spike in your Aquascape "Ecosystem" Pond. I am going to share with you what I am doing specifically in my own pond. Currently, my pond water is clear to the bottom of the 3' area. As long as you can see a dime on the bottom of your 2' pond, you have clear water. Remember, pond water clarity is different from swimming pool water clarity.
1. Yearly Pond Cleaning. Pumping out your old water, washing off the rocks, and cleaning out all of the organic leaf debris and sludge is a very important first step in reducing your nutrient overload.
2. Biological Filtration. The Aquascape Biofall is the "powerhouse" of your biological filtration system. The biofall is also your waterfall. It comes complete with two filter mats and bioballs. In the past, we used lava rock instead of bioballs, but lava rock is extremely heavy and hard to deal with when cleaning your filter on a yearly basis, so we are thankful for the invention of bioballs by Aquascape. To supercharge your biofall consider adding aquatic plants. We highly recommend the floating Water Hyacinths. These plants are excellent at absorbing excess nutrients. To keep your plants from washing down over the waterfall, consider adding either a piece of fishing string across the opening anchored by rocks (tie the string around a rock on each side) or use a decorative piece of drift wood across the front of the biofall opening. I prefer using driftwood. In addition, for large biofalls (6000 series or grande), add some aquatic plant pots (the kind with the holes in them) and fill them with river gravel and plants like Pickerel Rush, Narrowleaf Cattail, or Umbrella Palm (tropical). You can also use a floating aquatic pot like those offered by Laguna. This year we are experimenting with adding a flowering Fuchsia in the floating pot with Corkscrew Rush and a dwarf Umbrella Palm and so far I am impressed with the results. The Fuchsia seems to be thriving even though it is growing primarily in water. In addition, I added the Rapid Clear Filter Pads in between my regular biofall mats this season, and I really believe they are making a huge difference when it comes to trapping the suspended algae particles and keeping them from recirculating in the pond.
3. Beneficial Bacteria. Aquascape's beneficial bacteria is an absolute necessity for every pond. This is what "seeds" the biofall filtration media and all of the rocks and gravel in the pond. The bacteria will multiply and consume the organics that cause nutrient overload in the water. We highly recommend starting the spring season with the Cold Water Beneficial Bacteria for our region then you can go to the regular Beneficial Bacteria as the water warms up in early summer. Personally, I use more than the recommended dosage when I start up my pond in the spring; however, please don't hold me liable for that information (increase your dosage at your own risk!). Instead of adding the liquid bacteria once a week, I will add it 3 times per week for the first month. I've had no ill effects from using too much bacteria. I prefer the contractor's professional grade to the retail line. To learn more about professional grade products, check out our Pond Supplies page.
4. Ion Gen Electronic Water Clarifier. This is our modern-day String Algae Busting Machine! Thank God for new inventions and technology. I absolutely love this equipment, but it is not a substitute for using Beneficial Bacteria.
You must use both. Beneficial Bacteria attacks suspended algae and the ion gen attacks string (filamentous) algae. After you clean your pond, add the recommended dose of pond salt to your water for the health of your fish (it's like a tonic to them), and it also helps the chemistry composition of the water for the ion gen to operate properly. Set the ion gen only on 1 or 2; a very low level. Keep it there unless you start to see string algae accumulating on the rocks and gravel and then bump it up a number or two and monitor your water clarity. When the algae disappears, bump the number back down to 1 or 2. I keep mine on 2. Now, I'm not talking about the rocks taking on a slightly green hue (that is normal); I'm talking about the long stringy stuff that you can scoop out by the handfuls if left untreated. The Ion Gen sends out copper, zinc, and silver ions into the water to control the algea. Too much copper in the water can harm your fish and that is why Aquascape provides test kits so you can monitor your copper levels. So, setting your ion gen way up on 10 is not a fail proof way to eliminate string algae, because it could kill your fish, and it will also cause you to replace your probe on a a yearly basis!
5. Aquatic Plants. The general rule of thumb is 70%-75% plant coverage for a pond that is in full sun. Well, we all know that this is impossible during April and May because our plants have barely started to emerge from their winter dormancy and that is why it is so important to focus on Items #1, #2, and #3 and #4 until your waterlilies and other plants begin to grow again and take over the pond's surface. I personally prefer a pond that is in full sun, because most waterlilies and other aquatics thrive in this environment so adequate plant coverage is very important. Here is one of my favorite pictures of the yellow waterlilies in our pond during the summer. The lilies help to keep the water temperature cooler for the fish, and it offers them shade as well as a hiding place for protection against predators.
6. Feeding Your Fish. In the early spring, the water temperature is generally too cold to begin feeding your fish. Give them time to "wake" up from their winter hibernation and let them do what they do best: scavenge for food on the pond bottom. Koi and Goldfish are from the carp family; they are bottom feeders. They can help minimize the algae bloom cycle by eating the algae off of the rocks and gravel. When you do start to feed them, just do it once or twice a week so you are not introducing more nutrient into the cycle before the ecosystem is ready to process it properly. Overfeeding the fish is why many people have water clarity issues during the summer months after the ecosystem has already been set up.
7. Waterfall & Rock Cleaner. After doing all of the above steps myself this spring, I noticed that my rocks and gravel began to have an excessive amount of green growth on them, so I decided I would try Aquascape's Professional Waterfall & Rock Cleaner this season. We use this product during every pond clean out to help eat the algae off of the rocks while they are being pressure washed. I was very pleasantly surprised at the results. I sprinkled the recommended dosage along my entire marginal plant shelf. Immediately the product went to work disintegrating the algae from the rocks, but initially it seemed to work only where the granules fell. The next day the shelf was even cleaner. Three days later, I noticed the product began to clean the rocks on the 2' level of my pond (an area where I didn't even sprinkle the product). Here's a picture of my water clarity today. I highly recommend this product!
The Ecosystem Pond Advantage
I think the above steps are very simple steps to take to minimize algae bloom and enjoy clear pond water. I have been enjoying the pond lifestyle since 2003 (although we began installing Aquascape ponds in 1998). We have two ponds in our yard. One is 3,500 gallons; and the other is 1,000 gallons. I have tried many, many different products over the years including barley straw bales, barley straw extract, carbon, algaefix, and Microbelift just to name a few. We all want to know the formula that works best, and this is what I've found works best for my ponds. Remember, the basic structure of an Ecosystem Pond is one that contains the following five components.
- Mechanical Filtration (pump and skimmer)
- Biological Filtration (biofall/waterfall)
- Rocks & Gravel
Eliminating just one portion of this equation will throw your Ecosystem Pond out of balance and will cause water clarity issues. Please feel free to ask questions and comment below. We are here to help you.