Koi Pond

I know about koi ponds.

Is your pond green? At about 500 gallons the biggest problem you have is that koi need about 500 gallon PER FISH.

Been there, done that. I had 3 in a 300 gallon pond and one by one they all committed suicide... apparently they knew that the pond was too small and, in their tiny fish brains, they figured that there MIGHT be a bigger place, a better place, just over that edge. I saved one or two, for they tended to make their break during rainstorms, but in the end they all died.

Until you get to that point, you need to understand that koi, all fish, will eat when there is food. They have no memory of "I just ate", or "There will be food tomorrow morning". So when they see you they beg for food like they are starving. Tiny fish brains.

So, food in = food out. And all that fish poop is GREAT for growing algae, or other plants. The fish will eat most plants so good luck with that. Use big pots to protect the roots and place them high enough that the fish cannot get inside the pots, and top with heavy rocks. You will be amazed at how big a rock a koi can flip out of a pot to eat the roots of an expensive plant.

You will need to run an oversize filter and clean it A LOT, like every other day until you see some change in the water quality.
 
Continuing (hit the submit too soon). Forget about the algae on the sides of the pond, they will eat that.

Feed only when water temps are above 55. They can eat algae if they get hungry. Below 55 the bacteria that process ammonia are not active so all that food goes straight to deteriorating the water quality.

Feed sparingly. Only once per day, only about one floating bit per inch of fish IIRC. Any excess goes straight out the other end of the fish. That deteriorates water quality.

When the pond is first filled, it will turn green for maybe 4 to 6 weeks, I forget the exact number, like 58 days? That is how long the bacteria take to get started. If you buy a live submerged plant from a pond store (not pet store) you will import the proper bacteria and that time will be shorter. But the fish will eat the plant so not sure that is worth it. Just be patient and leave the algae on the pond edges alone, that is part of your filtration system. [edit] You can also get floating anarchis at the pet store, or some other sorts of plants. Be sure they do not have snails on them. You can submerge in a bath of Alum (forget what concentration) to kill snails without killing plant. Live plants LOVE the ammonia and nitrates that the pond is full of during the first few weeks.

Live plants will allow you to still feed the fish some during the break in period. Otherwise you need to hardly feed at all.

Do not add pond plants pulled from the side of the road. Been there, done that. Got anchor worm that killed some very nice fancy goldfish and cost $40 to treat by the time it was all done.

Pet stores are sometimes good, usually not. Maybe a dog person is tending the fish today. Some clerks get their education from the labels on the magic potions on the shelves (like some pool store clerks). There are a few good stores that I recall, I went from ponds to fancy (read that as expensive) planted aquariums (with discus, the most beautiful of fresh water fish, sort of an underwater peacock) and so my recollection of the pond places is very old.

Very important, when the pond is new and not "cycled" (the nitrogen cycle is not in place, the filter is not yet populated with the right bacteria) I strongly suggest using Prime water conditioner. Some areas have changed to chloramine instead of chlorine in the water. This is important, for if you use the wrong water conditioner, it may bread the chloramine into chlorine and ammonia, and then get rid of the chlorine, leaving the ammonia. Ammonia kills fish. "Prime" locks up the ammonia as well as the nitrates (just annoys fish but does not kill them) while treating the chlorine and leaving all the nitrogen products available to the plants and bacteria. You can use a small amount every day while the pond is new to keep fish safe for that first week or so. When you test for ammonia you need to use a specific type of test to see this bound ammonia, I forget, Nessler type? Check into that, read the label on the Prime or ask on the internet.

Prime comes in an indoor aquarium type and a pond type. You can use the indoor outside but not the pond type indoors as I recall. Much cheaper on the internet, but you can find at local pet stores until then. Go to DrsFosterSmith.com and to BigAlsOnline.com to get stuff you need.
 
Dora said:
Wow. That is a lot of information. Makes me glad I don't have a Koi pond.

The biggest lesson I learned from keeping fish ponds and aquariums is that you don't keep fish, you keep water. The fish take care of themselves as long as water quaility is good.
 
anonapersona said:
Dora said:
Wow. That is a lot of information. Makes me glad I don't have a Koi pond.

The biggest lesson I learned from keeping fish ponds and aquariums is that you don't keep fish, you keep water. The fish take care of themselves as long as water quaility is good.

Thanks for all that info a lot to take in. I finally drained the pond the other day and put in new water. You can actually see to the bottom now. When I first filled the water was very muddy and brown looking. It is now clear and you can see to the bottom. It seems dirty, but there is a black vinly liner that I am sure contributes to that. There is a port over the pond so no direct sun. So are there any type of test I need to do or what to get started?
 

Enjoying this content?

Support TFP with a donation.

Give Support
Don't worry about the dirty sides, if you get fish they will eat that algae growth. As long as it is just thin and not long and stringy you are fine. You will need a test kit for nitrates and ammonia when you add fish. You will need a dechlorinator, I suggested Prime Pond. Left alone, the chlorine will be gone in a day, but chloramine can last a month if untreated.

You must have a GFI protected outlet for your pump. Be sure the pond is level and that there will be no runoff from the roof during a heavy rain. Some shingles have zinc granules to retard algae growth, but that will damage fish. Debris or hard splash from the roof will mess with water chemistry. The edges of the pond must be elevated so that ground water cannot flow into the pond. Site the pond so you can stand on something firm to do cleaning. Nice to have a way to sit and sip coffee as you admire the fish and plants.

If you will have fish, you must have filtration and aeration. Select a pump with a nice size sponge filter on the inlet and perhaps a small fountain attachment. I preferred no fountain, just gushing water that went straight up, to minimize loss to splashing and evaporation. Splash will be occasionally twice the diameter of the height of the fountain, so look at the width of the pond and make the vertical spray less than half of that. So your fountain must have an adjustment on the outlet stem. There is some rule about pond turnover/hr to size pumps, you'll need to look that up. I think it is 2xpond size or 4 if you have koi or tend to overstock.

Expect 58 days of green water as the nitrogen cycle is established. If you want plants, buy them now and put them in, even before you put in the pump or stock fish. If the pond shell has shelves, make sure the pots are near but not above the water line. Plants add to the beauty, help clean the water as they grow, yet help foul the water as they die. Plants should be in dirt that has no organics like peat moss or sticks that will decay or vermiculite or pearlite that will float. Just plain dirt. With no direct sun your plants will be limited, no water lily for example.

When you decide what to put into the pond, stock 1" fish mature size per gallon of water. Since a koi can grow to 3', you see why you cannot have them. My favorite is the fan tail goldfish, mature at about 5" so you can have a lot of them. Comets and shubunkins are longer, to 10". In 500 gallons you can easily have 15 or more with a mix of fan tail and longer types.

Be aware that fishing type birds can clean you out in a day if the pond is shallow with no hiding places. I used black milk crates to prop up my plants and that gave the fish a good hiding place. Also, black PVC pipes are good.

Feed slowly sinking food or flake for goldfish. I know they want to sell you floating food but goldfish will swallow so much air they float belly up -- tiny fish brains, don't know when to stop eating. If you do have koi, they can handle the floating food, they are strong fish. You should not mix koi and goldfish, IMO.

And do not overbuy food the oils in fish food will be rancid in 6 months, from manufacture, not purchase. If you buy a huge bag of food and it lasts 5 years, you will kill all your fish, been there, done that.

Winter, here in SE TX winter is not much of an issue. It is wise to keep the pump off of the floor of the pond in the winter if you can manage that, for the circulation of the fountain through freezing air introduces sudden cold to the pond water. If the pump is off the floor there will be a warmer level down there. People with big waterfalls or fountains have woken up to find all their fish stunned and dying from water that has plunged in temperature due to below freezing winds super cooling the pond and no warm place to hide. It is rare for ice to form on the surface of the pond, particularly if the pond is buried and not above ground. Just don't feed when water temp is below 55.

Selecting fish. Be very picky about the fish you buy. Never buy from a tank with diseased fish, inspect the whole tank before selecting. Most fish stores have common filtration, so the sick fish in the tank at the corner may be infecting your fish. It is OK to pay $5 for a fish instead of $0.15 if you save $40 in medications later. Store will give you instructions in how to float the bag, introduce water to equalize chemistry (different hardness can really damage fish, newly shipped fish may be in nearly RO water) and temperature. Do not feed for the fist few days, let them eat algae, less ammonia to worry about. Add Prime every so often for safety. May as well stock the whole pond at one time from one source to minimize disease issues.

That is all, I think, about 20 years experience with fish ponds.

[edit] PS. NEVER NEVER NEVER add a plecostomus or any sort of sucker type fish with goldfish. When the aglae that they both eat is gone, the pleco will suck on the goldfish leaving a round mark that becomes infection site. Kills goldfish. Do not let them tell you that pleco eats fish poop, no fish eats fish poop. If fish poop still has food in it, then you feed too much and undigested food is coming out the other end. Aquarium catfish will not survive in goldfish tank, I've seen photos of catfish stuck in goldfish throat, fish died.
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.