Re: Dose rate check please.
Posted: Wed Jul 11, 2012 5:19 am
We to have sufferred dreadfully after dosing with FMG.......
Interestingly research - after the event- (hindsight is a wondorous thing!) reveals longstanding issues with malachite....
From 1 of the 1st hits..
"Add 100 ml of Proform C for every 1000 gallons of water to be treated. This dosage level produces 0.05 ppm of Malachite Green and 15 ppm (or mg/liter) of Formalin."
In the aquatic toxicity literature for pesticides, I find the 96 hour (4 day) LC50 (Lethal concentration that kills half the fish) for Malachite Green for carp is 0.1 ppm, or twice the actual dose labeled on a bottle of Proform C. The bottle label dose, however, is for a full dose for three successive days, or a total of 1.5 ppm Malachite Green if practiced at bottle label conditions.
So some folks do experience deaths when using Proform C at bottle label conditions. No wonder, since the dose is 50% higher than the 4 day LC50 for carp.
I don't use Proform C as the bottle labels. I use a full dose, wait 5 days, dose again, wait 5 days, dose again. This gives the Malachite Green a chance to be decomposed in the pond environment before the next dose.
Maybe the folks who throught they had problems with Proform C and salt just were seeing Malachite Green overdoses when using Proform C at bottle label conditions.
Comments, discussion? "
so I got hubby to check at work:
"Done a quick search curtsey of our aquatic ecotoxicologists and the article you posted to me may well be right. Couldn’t find anything that approached a reliable LC50 for carp, but there was some information in carp and lots of published LC50 s for other species. It has a log Koc of 0.6 l/mg so that means that the activated carbon will also pull it out of solution but it does not biodegrade or have any abiotic degradation pathways."
So basically in sunless weather without your UV running the malachite accumulates so each dose pushes the koi into the toxicity range ....unless you do massive water changes.
Our koi are looking 100% happier in a vat whilst we empty and refill the pond whilst trying to keep the filter alive by pumping across water from the vat to the filter..... however many will never be the same, 1 problem 3 have is downward turning eyes, these look awful but at least they are swimming and cruising in the vat, and the redness to the skin is settling down.
As you will see from the time this is written I am not getting much sleep! just been out to check water conditions in the vat as we have a lot of koi in 1500 gallons with just a protein skimmer running on it!
I for 1 will never use malachite again.
Interestingly research - after the event- (hindsight is a wondorous thing!) reveals longstanding issues with malachite....
From 1 of the 1st hits..
"Add 100 ml of Proform C for every 1000 gallons of water to be treated. This dosage level produces 0.05 ppm of Malachite Green and 15 ppm (or mg/liter) of Formalin."
In the aquatic toxicity literature for pesticides, I find the 96 hour (4 day) LC50 (Lethal concentration that kills half the fish) for Malachite Green for carp is 0.1 ppm, or twice the actual dose labeled on a bottle of Proform C. The bottle label dose, however, is for a full dose for three successive days, or a total of 1.5 ppm Malachite Green if practiced at bottle label conditions.
So some folks do experience deaths when using Proform C at bottle label conditions. No wonder, since the dose is 50% higher than the 4 day LC50 for carp.
I don't use Proform C as the bottle labels. I use a full dose, wait 5 days, dose again, wait 5 days, dose again. This gives the Malachite Green a chance to be decomposed in the pond environment before the next dose.
Maybe the folks who throught they had problems with Proform C and salt just were seeing Malachite Green overdoses when using Proform C at bottle label conditions.
Comments, discussion? "
so I got hubby to check at work:
"Done a quick search curtsey of our aquatic ecotoxicologists and the article you posted to me may well be right. Couldn’t find anything that approached a reliable LC50 for carp, but there was some information in carp and lots of published LC50 s for other species. It has a log Koc of 0.6 l/mg so that means that the activated carbon will also pull it out of solution but it does not biodegrade or have any abiotic degradation pathways."
So basically in sunless weather without your UV running the malachite accumulates so each dose pushes the koi into the toxicity range ....unless you do massive water changes.
Our koi are looking 100% happier in a vat whilst we empty and refill the pond whilst trying to keep the filter alive by pumping across water from the vat to the filter..... however many will never be the same, 1 problem 3 have is downward turning eyes, these look awful but at least they are swimming and cruising in the vat, and the redness to the skin is settling down.
As you will see from the time this is written I am not getting much sleep! just been out to check water conditions in the vat as we have a lot of koi in 1500 gallons with just a protein skimmer running on it!
I for 1 will never use malachite again.