Video - How to do a Freshwater Dip

How to perform a freshwater dip

fresh water dip.jpg

Freshwater dips are a very important diagnostic tool when you have a sick fish. Since it can help flush out the excess mucus that can and does build up in the gills with a parasite infestation, it can be lifesaving as well. It will even confirm a flukes infestation. It’s important to know how to perform a freshwater dip since so much can be gained from it. We are going to go through the steps here together.


· A container that holds water and is large enough for the fish in question to fit inside easily. It’s preferable to have a dark colored container to make finding flukes easier.
· Air pump, Air stone and tubing.
· RODI water (you can buffer the water with a splash of tank water)
· Net & Heater
· Cell phone, timer, stop watch, clock – something to keep track of the time.

These are all common things and I’m sure most of us have them laying around already.


· Fill your chosen container with RODI water and start heating it to match the tank the “patient” is coming from.
· Place an air stone in the container to start aerating the water.
· Catch the patient.
· Check that the temperature matches between the container and the tank. You can check the PH of both and if they are wildly different, use a splash to tank water to buffer the dip water a bit.
· Place the patient in the freshwater and start the timer for 5 minutes.
· Keep a close watch on the fish while the dip is in progress. If he starts thrashing about, it’s probably a good time to remove him from the dip early.
· When the 5 minutes is up, remove the fish and replace him either in the tank he came from or into a QT.

When you’re done, don’t get rid of the water yet! The first thing you will do is look closely at the water the fish was just in. If flukes are found, you’ll see opaque circles or ovals in the bottom of the bowl. If the bowl is clear, then flukes can be ruled out and other parasites or maladies can be considered. Take a look at the fish you just got done dipping. It’s possible that the fish is now breathing easier, a bit more alert, or just resting from the treatment.

For additional info on Freshwater Dips see Humblefish's write up here: Freshwater Dip

I’ve never had a problem performing a fresh water dip on a fish. I’ve done hundreds and only lost a hand-full of fish. I’ve found that if a fish doesn’t survive the freshwater dip, he was likely past saving anyway. That sounds harsh, but it’s likely true. Here is a video of how I perform a freshwater dip.

Special thanks to my coworker Sonia for being my camera-woman and to the customer to waited that last minute patiently so we could finish the dip and the video.

Discuss This Article Here
About author
Meredith Presley started keeping marine aquariums in 2007. She’s done everything wrong that can be done in the hobby (mostly but not all in that first year) and that has afforded her to learn a lot of hard lessons. Recently she’s been focused on marine disease diagnosis and treatment and hopes to focus on breeding soon as well. She also keeps a blog with basic info on saltwater keeping and her experiences with her own tank and livestock.

Article information

Last update
5.00 star(s) 9 ratings

More in Fish Disease and Treatment

More from melypr1985