Koi Water Treatment Experiment

Back in August I wrote about a new water treatment for koi ponds called Aqualibrium, which while I believed it could be effective in removing algae I was also sceptical about some of its other claims. Well the nice people from Aqualibrium contacted me and along with some more information sent me a bottle to try. I must say going on the first impressions, the aluminum bottle looks good but what I and many other koi keepers really want to know is does it work?

Now never one to turn down a free gift I was interested to give it a go, but the primary reason someone would buy this product in my opinion would be to get rid of algae and blanket weed, neither of which is a problem for my pond. This time of the year is not really ideal for trying a koi pond treatment as the temperatures are going down and with daylight hours getting shorter most algae will tend to die back by itself anyway. Having tested all the parameters of my pond water I realised that any improvements in quality would be difficult to detect without expensive and very sensitive equipment. The problem then is how do you test an algae treatment when you haven't got any algae? To be fair to Aqualibrium and in the hope of getting some dramatic results I've decided upon setting up an indoor test rig that will be more controllable.

Using a large vase of water I hope to recreate in miniature the conditions found in some koi ponds, starting by growing algae which shouldn't be too hard. With most of the organisms present except for the koi it will be possible to pollute the water beyond a point that would normally be tolerated. Before I start this experiment I have to say that I'm not a scientist and there may be a few flaws in my plans so even if the results are conclusive this shouldn't be taken as definitive proof. Really this is just a bit of fun and although I have a few theories I'm not totally sure what's going to happen.

Starting from scratch with fresh tap water and new filter media I shall go through the process of establishing a bio-filter which often causes problems for many beginners when setting up a koi pond for the first time. As Aqualibrium works by activating the microbes already present in a pond we need to first establish a healthy culture of the right bacteria. One of the main reasons that a pond turns green is because of the build up of nitrate levels produced from the nitrifying bacteria. By including a small filter in the vase that supplies an abundance of nitrates and given plenty of day light, algae should easily grow. I'll try to explain the processes involved in more detail later on.



I'm using a small aquarium filter that I replaced the foam with Fluval Biomax - a highly porous ceramic media, because this media provides a very large surface area for bacteria to grow on while it shouldn't trap the algae as it develops. By regularly feeding the system with koi pellets and testing the water I should be able to monitor any changes. Starting with chalky London tap water with a pH of 7.5 there are as one would suspect few impurities worth testing for but it's worth mentioning that nitrate levels are between 25-50 mg/l. This is perfectly fine for koi but it does show that when doing water changes you may not be reducing the nitrate concentration in your pond as much as you think. In fact in some ponds the addition of more nutrients in fresh tap water can be the cause of algal blooms.


To avoid this possibly becoming like watching paint dry I will update when anything significant happens. As well as a test of Aqualibrium this will also be a good opportunity to explain and try out certain theories of how a koi pond filter works and how you can improve yours.