Now that summer is in full swing, I have a pond full of fish (if only they were tilapia...), and the pond has had a few months to carve out its own little environmental niche in my backyard, I can share 3 important lessons that I've learned.
Lesson 1: Don't buy a pump with "pre-filters" or a "clean-water" pump. Buy a pump that can handle solids.
So, I started off with the Dynatec 1350 Pond Pump, because I wasn't really sure how many gallons my pond had, and I didn't want to get too much pump. After about a month, it became clear that I needed a stronger pump, so I got the Dynatec 1500 Pond Pump. It was the same size, which made swapping out the old for the new very easy, but had a little more power. Though I was impressed at first, I started having the problems with flow, and it turned out that the little sponge "pre-filter" was getting covered in algae and basically choking the pump. I could fix it easily by putting on a clean filter or cleaning the filter that was on there, but it started to become a hassle. I also noticed that if I just tried to clean the filter, sometimes I'd only get a day or two before it got clogged again.
So, I decided to upgrade the pump, and I went with a Little Giant K-3000 pump. It's bigger and a lot more powerful, but the nice thing is that it can handle solids up to 3/4" or so. Plus, the water in the pond is moving like crazy now, and I think that it finally might actually be turning the water over 1-2 times per hour like it's supposed to.
Here is the Little Giant. It was bigger, and ended up taking up a bunch more space. I took out the big green filter that comes with the skimmer and just put the leaf netting right in front of the pump. It's basically the first thing that anything coming into the skimmer sees. One benefit I've noticed with the increased flow is that the algae is getting sucked into the skimmer and is collecting on the leaf netting. Simple - pull the netting out, shake it a bit, and algae is gone!
That brings me to ...
Lesson 2: Gravel slows the water down a lot, so you need more outflow capacity than inflow capacity, because the water will be moving slower going out than it is going in.
Sure, this is something that makes sense and that I thought about before I put the system together, but I definitely underestimated how it all would work. The upshot is that when I attached the new, more powerful pump, all of my buckets were overflowing! I tried for a while to find the right setting for the ball valves, but I just couldn't find the sweet spot. In the end, I settled on extra drainage from one of the buckets using garden hose siphons. This brings me to...
Lesson 3: Make sure your buckets are level! And even if they start off level, they may settle. They may settle a lot!
Sometimes in the morning, I'd go out and check on things, and I'd notice that the water level was way down in the pond. Sure enough, I'd see some water trickling over one side of a bucket. Since those things weigh around a ton with gravel and water, there's no way of jacking it up to fix that, so the only thing you can do is turn down the in-flow to lower the water level. This only works so long until you don't have enough flow to keep the plants happy.
This happened to one of my garden buckets, but it also happened to the wetland plant bucket quite frequently. There was nothing else for me to do but redo the wetland bucket, and that's what I worked on this weekend.
Here you can see all the hose siphons coming in. Due to the settling of the wetland bucket (just out of the picture at the top and the settling of one of the garden buckets (off to the left but not in the picture), siphons were the only way to keep the water from flowing over the sides of the buckets.
And now on to the weekend's project - empty the wetland bucket (while trying to ensure the survival of all the plants in it), add in extra drainage, level it, reposition, add back all the gravel, rebuild the waterfall to accommodate the extra drainage, and then enjoy!
First, I removed all the plants and put them in this big cooler. I put some gravel in the bottom and filled it with water, just like how it was in the bucket. Only difference is that the water wasn't moving. I put the cooler under a tree so that it would have good shade during the heat of the day.
Then, I removed all the gravel from the bucket. If you've ever wondered how much gravel a 110 gallon plastic tub from Tractor Supply holds, well, there it is! If I remember correctly, it's about 8-9 wheelbarrow loads.
After taking apart the waterfall and a good bit of the rock wall surrounding the bucket (needed to do that to get the bucket out), I added sand and gravel to the bit of ground that the bucket sits on to help get it level. I also had to redo the waterfall to accommodate a new, low drain pipe. Pictured below are all three drain pipes (looking down). The top one is not necessary, but that was where the old drainage was, and I already had a hole, so I figured it wouldn't hurt to put an emergency drainage pipe there just to plug the hole. Also, all of my pipe is 1.5" pipe, but I added in a 2" pipe (PVC white in the photo) to ensure that the darn bucket wouldn't overflow ever again, even if it went off-kilter.
So, after the fish-safe, aquarium epoxy set for 24 hours, I filled up the bucket to test for leaks and see how things looked. Everything seemed to be working well, so I added the gravel back. After the gravel went back in, the water level wouldn't get any higher than the top of the bottom drain pipe! WHAT?! Before, it was overflowing - that was the whole point of this exercise - if I add in more drainage, then it won't overflow. But now, all of a sudden, it didn't need it! Frustrating. The waterfall is supposed to have water flowing down it!
So, after much pondering, I took a hose clamp and tightened it down on the end of the outflow pictured above. It got pretty tight, but it definitely worked, and the water level came up high enough to start to flow out the PVC tube and then down the waterfall! Sure, most of the flow comes out of the bottom pipe, but there's good water coming down from above, and it all blends in nicely. The sound is stronger than ever, and the fish really seem to like it.
With the water flowing well, I added the wetland plants back in, and the project was finished!
2 weeks ago