Volcanic ash is formed during explosive volcanic eruptions. This occurs when gases dissolved in molten rock (magma) expand and escape violently into the air, and also when water is heated by magma and abruptly flashes into steam. The force of the escaping gas violently shatters solid rocks and blasts it into the air, where it solidifies into fragments of volcanic rock and glass. Once in the air, our weather patens take over and wind can blow the tiny ash particles thousands of miles away from the volcano.
The components of volcanic ash are mildly corrosive and potentially conductive. The soluble coatings are derived from the interactions in an eruption column may be composed of sulphuric and hydrochloric acid and droplets with absorbed halide salts.
At the present time, the prevailing winds are driving the ash from the recently erupted Icelandic volcano south/ south eastwards. Predictions are that the ash fall-out will start to occur in Scotland tomorrow and move further southwards.
Although the silica content of the volcanic ash is considered non-toxic, the problem starts when there is a ‘sulphur’ component to the residue. Already, from some of the eyewitness accounts in Scotland, people have commented on the smell of rotten eggs (Hydrogen Sulphide). As the ash moves Southwards further over the UK, it would be prudent for those with pond covers to replace them for a short period. Koikeepers with uncovered ponds should keep a close eye on the fish. The addition of clay to the pond will help to buffer any reduction swings in pH due to the acidic content of the ash. Should any unusual behavior occur with the Koi, a water change using a purifier or the addition of de-chlorinator will help but keep an eye on pond water temperature changes.
It is not unusual for problems of this nature to occur. Earlier this year, sulphur dioxide was detected in blood samples we took in the West Country whilst investigating Koi mortality. This occurred after a period of northerly driven snow and rain.
If you need any further help, do not hesitate to give us a ring on 01243 572762 or 07726840627.
The Healthy Koi Team.