Fishless Cycling

When you add fish to your pond they will immediately begin to produce ammonia. It is a byproduct of their breathing, their waste and their uneaten food.

This is part of the “nitrification cycle“ which is natures way of creating and maintaining water quality.

When the ammonia builds up in the water, it is harmful to the fish and it can cause long term damage, make them ill or even kill them.

After the ammonia levels peak which is known as the “ammonia spike” nitosomonas (a good bacteria) will begin to develop and feed on the ammonia reproducing and multiplying in order to handle the ammonia load.

The nitrosomonas convert the ammonia into nitrites which is also quite detrimental to fish. Just about the time the ammonia levels drop down to zero, the nitrites will begin to spike. The answer to this problem is to grow nitrobacter.

Nitrobacter is another type of good bacteria which convert the nitrite into nitrate. Nitrate is harmless to fish in quite high levels and it is used up quickly by plants as a fertilizer which is the basic principal behind Aquaculture.

Aquaculture is basically hydroponics that use fish to benefit plants (rather than chemical fertilizers) and the plants filter the water to benefit the fish. A sort of co-dependant, environmentally friendly and organic gardening method. A whole different subject I hope to cover in the near future.

So, as you can see, the starting of the nitrification cycle in an artificial system is quite a process and not at all good for the fish to experience.

Your Options:

A) Add very small quantities of fish and gradually ad more over long periods of time allowing the system to gradually build up almost un-noticeably.

Not a bad option if you have a large pond and some patience. You can enjoy the few koi and really take your time in the selection of new fish and end up with a nice variety.

B) Add “mine canaries“. The sacrificial dime store goldfish to go through the rigorous stages of starting the filter.

This is my least favorable option and I don’t recommend it. Not only do I think it’s a bit inhumane, but you could be introducing a lot of long term problems into your pond with those cheap fish that could really get out of control in the less than optimal conditions of a new pond. These diseases and parasites would be carried over into your koi fish and could end up an ongoing problem.

C) Fishless Cycling: This is the best option but it requires a bit of patience.

I read somewhere in my research on a particular forum that fishless cycling was not a good idea for a koi pond because it did not produce heterotrophic species, the little rotifers and what-not that break down and deal with organic waste. Well if you check out the little video I created you can clearly see that that’s just not true. These heterotrophic species magically showed up almost immediately, long before my cycling process finished.

Hear are the steps to fishless cycling your filter system.

1) Start up your system and make sure you have at least a good nitrite, ammonia and pH test. The ammonia test will be used right off the get go. It can be a bit confusing to understand ammonia with the whole nH3/nH4 thing. If you need some help, I wrote a bit about that “click here”.

Now add all of the brushes filters matting bio-media, screens and so forth and start everything up except for the UV lights. Keep them off until everything’s properly functioning and the bacteria’s are growing in the bio-filter as well as on the surfaces of everything.

Beneficial bacteria prefer a pH of around 7.5 to 8. so it’s a good idea to monitor your ph throughout the process. I added Crushed Coral to stabilize my pH which also acts as an additional bio-media.

2) In an ideal situation you can go to someone you know who already has a well functioning filtration system with known, quality, disease free healthy koi and borrow some bio-filter media from them to place in your filter. This will reduce the process time by many weeks. The only danger in this is if they have (still unaware) anything creepy, hiding deep within their system, you will be introducing it to yours!!! So trusting your source is crucial. Also, treat the filter media as though it were a live fish that needs timely transportation, temperatures, oxygen, protection and fresh water.

I personally, due to the fact that I will be selling koi and my reputation is of utmost importance to me, opted for the painfully slow method of growing my system without someone else’s filter media for seeding it. Although I did add a bottled product which you can read about in my fishless cycling journal.

3) Add ammonia: The idea is to create an artificial fish load so whereby giving the nitrosomonas a food source and encouraging their growth.

You want to be sure the ammonia does not have anything in it except ammonia. In my research, I read that you can shake the bottle and watch for suds. I bought two different bottles of ammonia. one turned out to say right on it in tiny print “surfactant” which is a form of soap. The other seemed all good with no suds. I called the number on the bottle though and asked for the unlisted ingredients. A few days later they called and it also had soap in it. The other thing with bottles of ammonia with no ingredients is how much ammonia is in one brand from the next? The one I had called was 2% ammonia.

In the end I used powdered Ammonium Chloride which takes all of the guess work out of it.

1/8 cup NH4CL (Ammonium Chloride) = 1oz. = approx. 1.33ppm (parts per million) per 1000 gal. of water

Bring the ammonia level up to about 5ppm

4) Now it’s a waiting game. monitor your ammonia level and occasionally your pH. when the ammonia begins to drop start testing for nitrites. The nitrites should climb before the ammonia hits zero. If the ammonia gets low 0.0? or so add more ammonia to give the nitrosomonas food while the nitrobacter grow. At some point the nitrosomonas will be numerous enough to handle an adequate fish load at which point you will be adding ammonia every day. Unfortunately, to my knowledge you cant buy any sort of nitrite so you have to wait for the nitrosomonas to produce it from the ammonia and the nitrobacter growth will not begin until the nitrosomonas are doing their job.

5)When the nitrite hits a stable “0” you are at last ready for fish.

There are a few places I’ve found on the Internet where someone recorded their fishless cycling process, however I found very little information for doing this with a koi pond in particular.

I kept a journal throughout my fishless cycling and found it to be quite different in some respects than that of others with fish tanks so I copied the more important entries "click here" for a guide in your possible efforts.

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