The power of UV

[schildkoi]

Quote: Originally Posted by koibooi Hey JasPR - why are you talking about Florida specifically? I live in sunny South Africa on the southern tip of the African continent and about 18 hours flight from Florida. Filter cleaning regime is great but you might have hit the nail when you mention Phosphates. I have a Hanna Photometer for Aquaculture (see link below) that I use for all my water analysis. When I use the Phosphate Low Range measure, I am always above the maximum reading allowed 2.50 mg/l. I am however not sure what an acceptable Phosphate reading is. HANNA instruments® :: Bench

koiboii,
Ahhhhh, perhaps we are getting somewhere? I am not sure of the direct effect on the koi for the levels of phosphates but phosohates are a direct nutrient source for algae.....and one that our typical filter systems will not handle. Any chance for adding a source water filter designed for phosphates (and possibly anything else that may be in the source water)?

I knew you filtration system should be handling the job (under normal circumstances) and it is reasuring to me (but no help to your pond) that the possible culprit (phosphates) may have been identified.

Steve

[JasPR]

Koi booie, I was talking to Mike M who lives in Florida. Phosphates are likely from your koi food, some brands are very high in phosphates. To find if this is a problem in your pond also monitor nitric acids ( nitrate) and you might find you have a problem with food brand and secondly from an over active nitrification cycle. Is your pond crowded? JR

[tangigi]

Quote: Originally Posted by koibooi In my case there is definately not a lack of filtration nor do I have too many fish in the pond. I have a seriously big filtration system holding 400 liters of K1 in two Nexus's as well as a trickle filter holding another 200 liters of bio-balls. The 30 ton pond only hold 15 koi with an average size of 70 centimeters. The problem was definately non-functioning UV's. I would not agree that if the UV is burning it is working. In my case all three of the UV's were in fact emitting a light. The light was fairly dim but it was on and shining. As soon as I replaced the ballast, using the same UV tube, the light turned from its dull shine to a bright shine. I do not know if there is a way in which one can measure the output of the transformer in the ballast but I would recommend that you replace the ballast and see the difference on the brightness of the UV. It certainly sorted out my problem.

strange indeed. i turned off my uv since I was planning to change the ballast. while waiting for the parts, the emerald green water cleared by 50% percent to a light olive color after 5 days. I can now see 2 and a half feet down.

temp in the tropics constant at 85 degree, have not rained.

could the algae have died off bec they were not getting any nutrients since the uv is not killing any organism? what could have caused the improvement in water clarity when I turned off the uv.

24,000 gallon pond totally under the sun, 17 fishes

if you want to see the inside of an aqua uv ballast. ballast is made in EU

my home made ballast housing