• Hi Darla,

  Sorry it took me so long, this time of year is a bit crazy for pond builders. We are busy cleaning and opening ponds right now. Everyone wants their beautiful pond and waterfall open as soon as possible to take advantage of the warm weather. In regards to your question about number of fish, there are some rules of thumb that I’ve heard, such as one inch of fish per square foot of pond area, or is it one inch of fish per gallon of pond water? I’m not really sure, I always tell people to use their common sense. Understand that with a new pond (and new pond owners) there are many unknowns. Is your pump going to work as expected? Is all of your piping correct? Will you have unforeseen leaks that need to be fixed? After you’ve installed a few ponds, most of these questions won’t be an issue, but there is always the leak possibility. In any event, I tell new pond owners to buy a bunch of cheap fish to start with, just to get the pond going. You can always add or subtract fish later. With your pond size, I would go find two dozen small goldfish and throw them in for starters. That way, no matter what happens, you are not out a lot of money. Once all of your construction work is complete, and you are certain that your pond is functioning well, go pick out some larger, nicer fish to fill in. Remember, fish grow. Don’t sweat the exact number, your fish load will be constantly changing as your fish grow. Once your pond is stabilized and running well with no problems, then go pick some nice fish of your choosing. Most people that I know have a mix of Koi, goldfish, sarasa, shebunkins and red rosies. If you truly have 5000 gallons of water, you will be able to have quite a few fish depending on their size. The amount will depend on the type of fish that you are buying as well. Koi get much larger than goldfish. You can keep many more goldfish long term than you can Koi. How much will you be feeding your fish if you feed them at all? The more you feed the fish, the less you will be able to keep. Why? Because the more food that they eat, the more waste that they produce and the more that they eat, the faster they grow. Also, the more that they eat from you, the less likely they are to forage around and find food on their own. Every pond owner is different. I have clients who feed their fish twice a day, twice a week, twice a month, or never. I personally never make a point of feeding my fish. I strongly believe that hungry fish make for a clean pond. Now, if your pond is brand new and really clean, you may want to feed your fish to get them started, but do so sparingly. The only time that my fish get fed now is when we have some little kids over, sometimes my kids will ask to feed the fish just for fun to show their friends. This probably happens 3 or 4 times a summer. The fish eat debris and algae from the bottom of the pond. Now, on the other hand, if you want the biggest, most colorful fish and you have a name for each one and you can imagine no greater joy than to sit at the pond and feed your fish, then go ahead, feed the fish. But in this case, you will need more water, water flow, and filtration to handle the heavier waste and food loads. Remember, any food that they don’t eat will serve to fertilize the algae. Wow, there you go, to make a long answer short, you will know if you have too many fish and it is not likely to happen until after years of growth unless you really spend a lot on fish. Also, remember that every new fish introduced to your pond may be sick and could potentially get the rest of the fish sick. Koi Herpes Virus is a very real threat and can clean out a pond quickly. Always buy from a reputable supplier and it is always a good idea to quarantine new fish.
  Now, on to the question of Koi ripping up the plants. I have never had this problem, but I’ve known a few pond owners who have. The people that have had the problem have had big Koi, I’d say 2′ or larger. I met a woman who had a big pond full of huge Koi and water lillies. She fed her fish twice daily just to keep them from eating the water lilies. But this is rare from what I’ve seen. If you start with smaller fish and plant your plants directly into the gravel of your pond, they will usually have enough time to establish themselves before your fish get big enough to rip them up. Many people leave their plants in pots, I never do. I plant lilies and marginals right on the rubber. Usually in a nook between two rocks. Then I cover the newly planted roots with gravel or small rocks. I hate the look of plastic pots and I want the roots to spread throughout the pond. More roots = more plants = less nutrients for the algae to grow = happier me. Once the roots spread throughout the pond, you won’t have a problem with the fish killing plants. They will surely eat some, but if your pond is well balanced there shouldn’t be a problem.
  Favorite pond plants? Well, that all depends. Personally In a pond of about 5000 gallons I would start out planting 4 or 5 water lilies of various colors and about 33 marginals and a hand full of submerged oxygenators in the pond itself. I would plant additional plants in the stream and many more in the wetland if I were installing one. This is a lot of plants, so you will have plenty of opportunity to experiment with many different varieties of plants to see what you like. Personally, I would start with plants that are known to be very hardy in your area. Ask a local grower for suggestions. You want these plants to grow and flourish without fertilizers or special care. Low maintenance! After you’ve established a base of plants, then you can experiment with some of the more touchy or delicate plants. Many people love to plant tropical plants for a great summer show and then bring them in for the winter, but that is too much messing around for me. Fast growing plants will be taking in more nutrients to grow, but will also spread faster and be harder to control. Go for a lot of plants at first to get the pond going, thin them out later as you see fit. Find someone who has an existing pond, they would probably love to rip out some of their plants to share with you. In the stream, I love the water celery and the aquatic mint because it grows so fast, but after a few years, you’ll be ripping it out and throwing it away. I would avoid planting floating heart in any pond. We made the mistake early on. Floating heart is pretty and fast growing, but will very quickly become a nuisance and is very hard to eradicate once it gets established. Cattails, although beautiful, can also be hard to control. I have them in my pond and I love them, but I also rip out large chunks in the spring when I start my pond. The roots are thick and may require a pruner or knife to cut which is not easy once mixed with gravel and on top of rubber.
  On to the question of the winter months. The donut shaped 100 watt heaters have proven to be not very reliable, the 1200 watt floating heaters work well but are expensive to run and provide no aeration. We have been using bottom aerators or small solids handling pumps in the winter to keep a hole in the ice and aerate the water.

  Good luck,
  Doug

  • May 09, 2011 4:16 AM
  • By admin

• Thanks for all the great advice! I really appreciate your willingness to share your pond knowledge and experience. Is there a good rule of thumb for the # of fish? Do you have any problems with the Koi tearing up the plants in your pond? If you do, how do you keep them out of them. I am hoping to have water lilies, but I’ve heard that Koi will eat them. What are your favorite plants? Do you have to run a heater in the winter months? I’m getting ready to order my pump. I want to have a pretty good flow of water for my falls and it’s about 40 feet from my skimmer up to the top of the falls so I’m going to get a pump with a high lift capacity or I’m afraid I’ll be disappointed with the water volume.
  Thanks again for your help.

  • April 25, 2011 9:25 PM
  • By Darla Grimm

• Hi Darla,

  Welcome to the wonderful world of water gardens! Congratulations on installing this one yourself, it sounds like quite a project. First off, let me say that over the years, I have discovered that this pond building/keeping business is a lot more common sense than it is technical smarts. It sounds like you have a great start with the pond that you’ve installed. I wouldn’t get too crazy with worrying about all of the gadgets. I’m sure that UV lights work to some extent, but I’ve never been a believer in using them in a pond. The cleanest most trouble free ponds that I have had the pleasure of knowing were always well balanced eco-system ponds. These ponds have always been loaded with plants. The more aquatic plants that we put into the water to take the nutrients out of the water, the less algae we’ll have. Simple right? People spend so much money on the latest blend of bacteria, enzymes, chemicals, clean out valves and UV equipment hoping to take a shortcut around the ways of mother nature, when what they really need to do is to have patience and realize that this is a pond, not a swimming pool. Ponds need a balance of water flow, biological filtration, plant material and fish. That is it, no big secret. You really don’t even need the biofalls and skimmer. These are just easy ways for the beginning ponder to get started without having to dream up a filtration system. The one mechanical piece that you do need is a pump. In my time I have found the Tsurumi pumps to be the most dependable and I use them almost exclusively now. They come in many different shapes and sizes and have worked well for me. Regarding pump sizing, every pump has a rating regarding how much water it will pump to what height. The general rule of thumb is to recirculate your water once per hour. Now That rule of thumb will do just fine, but it may be a bit of overkill depending on your pond. The more fish that you have, the more circulation that you need and the more filtration that you need. With moderate fish loads and lots of plants and filtration, you can do just fine with much less circulation. When I first built my pond, I had about 12,000 gallons per hour of flow going to my two streams that fed about 10,000 gallons of water. Now I knew that I was over doing it a bit, but I wanted to see a lot of water flow. Years later, after my original pumps had died, I started experimenting with different used pumps. Basically, whatever I had laying about from jobs that I had done. For the last two years, I have run the same pond on 6,000 gallons per hour and it looks the same in terms of water quality. The waterfalls aren’t as dramatic, but you wouldn’t really know unless you had recently seen the old falls. I don’t even really notice, and I cut my electric usage by at least half. Start with your one biofalls and one pump, skip the UV, plant lots of plants, add bacteria, add fish and see how it goes. Remember to have patience, the first two years with a new pond are the hardest. No matter what, don’t resort to dumping in all sorts of water treatment products, that will just screw it up. Bacteria, nothing else. The plants will grow, the roots will spread and in a few years you’ll barely need to touch your pond. By the way, have fun!

  • April 21, 2011 4:00 AM
  • By admin

• Hi Doug,
  I’m a newbie in the pond world. It’s always been my dream to have a pond and a waterfall in my yard. Last year was the beginning of my pond adventures. I have approx 5,000 gal pond, 3.5′ deep at the center with a 5 tiered waterfall course approximately 25′ in length with a header height just above 12′. I installed a skimmer that can accommodate 2 pumps and so far we have the water line installed for a biofalls to the top of the waterfall. Originally I was only going to run the one pump, but I’m worried about the energy consumption running the falls constantly so I’m thinking it would be better to run one smaller velocity pump all of the time and the waterfall pump just when we’re here to enjoy it. I guess I’ll have to install another biofall and run another line maybe to the first drop of the falls into the pond in order to have enough oxygen. What do you think? Also I haven’t purchased my pumps yet. I’m hoping to get some help with choosing the best pumps for my situation as I’m really unsure what to get. Any suggestions? I plan on getting a couple of UV lights to add to my skimmer also, but I have to wait another month or so to purchase them. There are places inside the skimmer to mount them, so do I have to consider the water flow rate for my smaller pump for the UV lights to work? Thanks for any help you can give me.

  • April 21, 2011 2:12 AM
  • By Darla Grimm

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