This page covers various issues and questions that I have received recently.

Magically Appearing Fish
Floating Liners
Dirt Ending up in Ponds - runoff and spilt plant pots

Other mystifying aspects of ponding are covered on other pages on my site. For example, on my health question page, I have answers to "Where did my fish go?," "Why did my fish die?," and "Why is my fish bent?" among other things. On my water chemistry page is a section on dealing with pond poisonings including oils.

• The fish were added to the pond as eggs or fry attached to some live plants that were added to the pond.
  
• A person, unbeknownst to you, added the fish to your pond.
  
• The fish ended up in your pond during flooding that washed them into the pond.
  
• The fish came to your pond as fish eggs that were attached to the legs of animals that visited another pond before yours where they picked up the eggs. For example, eggs may stick to the legs, fur, and feathers of herons, raccoons, and most mammals and birds. This is pretty common.
  
• A predatory bird had a fish in its mouth from another pond and accidently dropped it in your pond.
  
• Sometimes fish change appearance over time so that a fish that you added a few years back may look like a new species or individual when it is not. Goldfish change color throughout their lives and koi to a lesser extent.

First, is there water or air under the liner. If it's air, then you may need to lower the pond level and slowly push the air along so you can work it out from under the liner. Most air is squeezed out when a pond is filled with water. If the liner is floating up because of water, you have to consider the causes. Here are some possibilities.

• 1. Cause - a high water table. If the water table is high, then water pressure from underneath the liner will push up on the liner. Sometimes, the water table is only high after a heavy rain or flooding. In some areas (low altitudes), the water table may always be high.
  • 1A. Solution for temporary high water tables due to flooding:
    The water needs to be drained from under the pond. If this happens every time it rains, a drainage system can be built under the pond. Pull out the liner. Pump out the water with a sump pump or vacuum it up with a wet/dry vacuum. Dig trenches. Lay in PVC piping with holes in it. Run the piping out to a level lower than the pond. Fill in the rest of the trench with pea gravel. Put the liner base and liner back into the pond. This will hopefully run the water away from the pond.

  • 1B. Solution for permanently high water table:
    I am afraid in this case, if when you did a hole, it always fills with water, you really cannot dig a pond down into the water table. As an alternative, you can build an above ground or mostly above ground pond. These can be build with wood or cinder block supports that are covered in a protective fabric or something and then the liner.

• 2. Cause - Water coming from a source other than the ground.
  • 2. Solution -
    You need to find out where the water is coming from if it is not coming from the earth or rain itself. It might come from broken water or sprinkler system pipes.

Dirt normally enters a pond when it rains. Here are some ways to prevent and treat that.

Prevention:

• Construct the pond on high ground, not in a low area of the yard if at all possible.
  
• Raise the rim of the pond a few inches above the surrounding ground.
  
• If you have an uphill neighbor, try to impress upon them how important it is to have stormwater management in effect (where the water will go) as well as how important it is to not flush toxins downstream (to your pond and natural waters). That means that you do not want to use fertilizers (cause algae blooms), pesticides (kill fish), herbicides (kill plants), petroleum products (oil and gas), etc. where they might run into your pond or natural waters.
  
• If the pond must be at a lower grade, then build a drainage system. This entails digging a trench at the higher end of the pond parallel to the pond. Dig down a foot or two in most cases. Line the bottom with gravel. Then, put in PVC pipes with holes on the top. Top off with more gravel and then sod or more rocks (rocks work better but may not look right). Run the pipes around the pond and downhill. When rain and runoff come towards the pond, they will go down through the rocks, into the pipe, and then downhill away from your pond.
  
• If you have a drain spout that will accumulate water above the pond or run into the pond, attach piping to the spout and run piping down below the pond. We have that on one of our drain spouts. Without it, water would pool above my pond. It still does some as some water runs up and over the gutters.
  
• For small muddy areas at the high end of the pond, you can remove the dirt there and replace it with liner. Lift up the main liner if possible to a higher level as well. With my 1800 gallon pond, one spot seemed to run in more dirt than elsewhere so we removed the dirt, lined it with an extra piece of liner, and put in more rocks over the liner. It seemed to help.

Treatment:

• Check around the edge of the pond for where most of the dirt is coming from. The liner can be raised there or other diversions put into place to run the dirt away from the pond instead.
  
• Increase filtration, adding finer filtering materials. Squirt them off regularly to help collect the dirt.
  
• If chemicals are added along with the dirt, put some fresh, activated carbon in a mesh bag in the filter to help remove those chemicals. Change the carbon in a few days with new carbon until the problem passes.
  
• Dirt will normally naturally settle over time. At the same time, water movement is needed for filtration and oxygenation so it will take longer with water movement for dirt to settle. Once settled, dirt can be removed by electric pond vacuums (will not work with venturi pond vacuums which use in-pond filter socks that dirt goes right through) or wet/dry shop vacuums (the pond level must be low to use that kind of vacuum).
  
• A quick and temporary fix for water cloudy due to dirt/soil is to add AccuClear by Aquarium Pharmaceuticals or other such polymeric coagulants. This will cause the dirt to clump and sink or be sucked into the filter. Be sure to maintain good aeration while using it as it does lower the oxygen usage abilities of fish.
  
• Work on the pond to prevent future problems (see prevention above).

Dirt Entering a Pond from Other Sources:

Dirt may also end up in the pond when dirt/soil is used to plant up aquatic plants. Such pots can easily be tipped over by various animals in the pond. Raccoons love to knock over pots in my pond. Pots should be topped with pea gravel to prevent dirt entering the pond by fish rooting in the pots. If the pots are knocked over, the gravel may end up in the pond anyway. Heavier pots are less likely to fall over. If animals cannot be prevented from knocking over plant pots, consider potting with 100% pea gravel or using commercial aquatic plant soil which is a brown cat-litter like soil that makes less of a mess and will not cloud the water very much when spilt. It does not secure the plant as well though so when the raccoons knock over such pots in my pond, the plants are usually floating around free. Treatment for dirt from pots is the same as from runoff listed above.

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