It is always difficult to know what to do when a fish in the pond shows
small areas of red inflammation and raised scales. Taking the fish out of
the pond and putting it into a sick tank is stressful. Sick tank water
quality can be very hard to control especially if you add a whole water
antibiotic (many fish die in sick tanks because of high ammonia levels).
Injections are best for very sick fish but we all don't want to see our fish
get to that point.
Trying to treat one or two fish in the pond is hard. Home made medicated
foods are only marginal, lots of the medicine washes off, never sure how
much gets into the fish etc. Commercial medicated feed is better but
expensive, short shelf life. Medicated food also treats all the fish, not
just the ones that need it. Putting lots of medicated food into the pond
also runs the risk of getting resistant bacteria. You never want to expose
bad bacteria to low doses of antibiotics, you just select resistance.
I have found a great solution! I have trained my fish to eat frozen peas as
a treat. They love them and it is fun feeding one treat at a time to the
individual fish. The larger size (less expensive) peas are easy to store and
to get out of their frozen bag. Warm then a little then feed away.
If a fish shows any red lesions, raised scales I immediately start putting a
small sliver of Cipro (ciprofloxacin either 250 or 500mg/tablet) into the
center of the pea. I use a very sharp utility knife/razor blade to cut the
tablet into very small slivers. A sharp point cuts a nice slit into the
frozen pea, wiggle the blade to open the slit and then push the medicine
into the slit. Use you fingers to close the slit and you have a pea you can
direct to the fish the needs it! I use non-medicated peas to give to the
other fish and to scatter the fish out so I can select the ones needing
medication. A small net on a long pole helps herd the fish and retrieve
pills the are not eaten.
I feed the medication once a day. It may take
10-14 days for complete healing. Continue till the fish is completely healed
or you may get a recurrence. Other antibiotics should work as well but Cipro
is widely available post anthrax scare. Many doctor's offices get sample
pack with two pills, enough to treat several fish.
If a fish isn't eating well then you have waited too long, an injection is
the only hope. The beauty of this method is you can start at the first sign
of trouble. In three years I have not had a single fish death and no fish
has had to get injections. I did put one fish into a heated sick tank during
the winter because it was too cold to feed. In the sick tank I fed the peas
and the fish did well.
The recommended dose for fish is 5mg medication/Kg fish weight once every one or two days. There is good data available describing the drug concentration and half life of enrofloxacin (Batryl) in fish. Batryl is one of the KoiVets preferred injectable medications. In an animal it is converted to ciprofloxacin which is the human version of the medication. At 50F the half-life of the medication is 48hrs, at 75F it is 24hrs. If the water is cold you can feed every two days, if warm I would feed every day.
As 500mg Cipro tablet weighs 765mg with filler. A very small flake will have 5-10mg cipro in it. That is enough for a fish about 17" long. Here are two tables I found that estimate weight based on length from nose to tip of tail: Estimating weight The safety margin is very large for these medications. A dangerous dose (in mammals) is about 100mg/Kg every day for 5 or more days. You will loose some medication when they chew the pill and some will not be adsorbed in the GI tract. I think over loading the peas is safe and makes sure you get enough into the fish. If a fish does not like the taste of the cipro try a larger pea or a smaller dose. Frozen cocktail shrimp cut side ways and then opened also appeals to some fish.
Below is a picture of a 500mg Cipro and two large flakes that weigh about 25mg each (about 20mg actual cipro) These two flakes are about 1-2mm thick, 4-5mm long. They can easily be cut into half or thirds which is enough for medium size fish.
The flakes look larger than they really are, only 1-2mm thick
A frozen pea is along side also!
AS WITH ANY ADVICE I CAN NOT GUARANTEE THIS, USE AT YOU OWN RISK!!
If this was helpful email me
My web site describing a very simple but efficient plastic and PVC "Koi Dome" top keep the pond ice free is also worth looking at. I attribute our zero fish death to the dome and the early medication. ALL our friends have at least one fish death a year. Koi Dome
Brad S