How To Freshwater Dip

[Humblefish]

Freshwater Dip (updated 3-6-2023)

What It Treats: Provides temporary relief of some parasites - Marine Velvet Disease, Brooklynella hostilis, Uronema marinum seem most susceptible to the osmotic shock.

A FW dip can also be used to dislodge certain crustaceans and worms, such as Parasitic isopods/copepods, Turbellarians and Flukes (Monogeneans). With Flukes, some genera (e.g. Neobenedenia) will turn white and be visible both during & after the dip (see video + photos below).

What "Freshwater" To Use: There are 3 options:

1. RO or RODI (add a little saltwater to improve conductivity so that pH can be read accurately)
2. Water taken from a "clean" freshwater aquarium (non-acidic i.e. pH should be 7 or greater)
3. Dechlorinated tap water (non-acidic i.e. pH should be 7 or greater)

^^ With all of the above, pH should be raised to ~ 8.0 before placing fish in the dip water. This can be accomplished by using supplements (available at most LFS) or you can “bake” your own DIY supplement by using baking soda. Spread baking soda onto a clean baking sheet, and bake at 300F for 1 hour. This process drives off carbon dioxide and water from the baking soda, and the result is an effective pH booster. You will need to experiment (start with a very small amount) to determine how much is needed to raise your pH to the desired level.

How To Treat: Fill a bucket with freshwater, and use a heater to match temperature to the fish's source water. Aerate the water heavily (by using an airstone or small powerhead pointed towards the water surface) for at least 30 minutes prior to doing the dip; and then reduce (or even discontinue) aeration while performing the dip. Place the fish in the freshwater (FW) dip and observe closely. It is not unusual for them to freak out a little at first. Also, certain fish (e.g. tangs) are notorious for “playing dead” during a FW dip. The important thing is to watch the fish's gills (they should be breathing heavily), and keep the fish upright & swimming at all times! If breathing slows, or the fish refuses to get up after chasing (BUT NOT TOUCHING) it with your hand, then it’s time to exit the dip! Dip the fish for no more than 5 minutes. Multiple dips may be done, but it’s important to give your fish 24-48 hours to recuperate in-between freshwater dips.

For Flukes, use a dark (preferably black) bucket so you can see if white sesame seed looking flukes (photos below) fall off the fish. The dead worms will settle to the bottom, so you can use a flashlight to look there as well. Some flukes (especially Neobenedenia) are able to be seen with the naked eye; gill flukes would require microscopic examination. So, post dip let everything "settle" and then use a pipette to capture anything that might have come off the fish (also take samples off the bottom to examine under a microscope). See also: Flukes under microscope

Pros: Provides temporary relief for a wide range of parasites/worms in a chemical free environment. Can “buy you more time” until a proper treatment can be done. A light dose of Methylene Blue (0.5 ml per gallon) can be added to the dip, if desired.

Cons/Side Effects: Not a permanent “fix” for any disease, as FW dips are usually not thorough enough to eliminate all of the parasites/worms afflicting a fish. (So, followup treatment in a quarantine tank is a wise course of action.) A freshwater dip SHOULD NOT BE DONE on weak/dying fish as it tends to "finish them off". Other fish can have an adverse reaction, once returned to their aquarium, by appearing unable to maintain their equilibrium. If this happens, hold the fish upright (using latex, nitrile or rubber gloves), and place the fish in front of a wavemaker (ON LOW) to get saltwater flowing through the gills again.

Video by Meredith Presley



Dead flukes in a freshwater dip:

 

[Denise]

I have a ? I had two clownfish a wyoming white and a davanci in my new tank I was using them to help cycle my tank. both fish are now dead .my tank is empty other than livesand and some rocks which are not live. I was originally told they died from gillsfllukes now one of the local fish stores is saying more than likely it was Brooks . my ? is what do I do with my water now ? and how long does it take to kill either one of those diseases ?
thanks in advance Denise

 

[Humblefish]

I have a ? I had two clownfish a wyoming white and a davanci in my new tank I was using them to help cycle my tank. both fish are now dead .my tank is empty other than livesand and some rocks which are not live. I was originally told they died from gillsfllukes now one of the local fish stores is saying more than likely it was Brooks . my ? is what do I do with my water now ? and how long does it take to kill either one of those diseases ?
thanks in advance Denise

You will need to go fallow (fishless) for 6 weeks to starve brook out of your DT.

 

[Daiseyreef75]

@Humblefish I have a question as a new reefer, obviously there’s a difference between best practice and what is accessible. I was wondering the effectiveness of using freshwater dips to treat fish with marine ich or other diseases.
As a new reefer cycling and water parameters were an issue, so proper quarantine of anything wet was more problematic than practical.
I’ve employed ich management with a UV and tank husbandry. But I was wondering when I see signs or to remove flukes etc. would freshwater dip without QT and treatment promote positive effects or excess stress? (use of fuge as acclimation after, until equilibrium is right)?

 

[Jposch]

@Humblefish I have a question as a new reefer, obviously there’s a difference between best practice and what is accessible. I was wondering the effectiveness of using freshwater dips to treat fish with marine ich or other diseases.
As a new reefer cycling and water parameters were an issue, so proper quarantine of anything wet was more problematic than practical.
I’ve employed ich management with a UV and tank husbandry. But I was wondering when I see signs or to remove flukes etc. would freshwater dip without QT and treatment promote positive effects or excess stress? (use of fuge as acclimation after, until equilibrium is right)?

Check out peroxide dosing. That would fit your management much easier, and likely more effective. Use the search box in upper right. You won't have to attempt catching all of the fish that way. Peroxide is essentially an aqueous oxidizer like uv and ozone. But, instead of being limited to just the small reaction chamber, it can reach most all of the wet surfaces. I've used it myself for alage, and also to buy a few days time to set up a QT, but never as a full management protocol. Others have shared thier experiences under the Peroxide dosing thread.

 

[Humblefish]

@Humblefish I have a question as a new reefer, obviously there’s a difference between best practice and what is accessible. I was wondering the effectiveness of using freshwater dips to treat fish with marine ich or other diseases.
As a new reefer cycling and water parameters were an issue, so proper quarantine of anything wet was more problematic than practical.
I’ve employed ich management with a UV and tank husbandry. But I was wondering when I see signs or to remove flukes etc. would freshwater dip without QT and treatment promote positive effects or excess stress? (use of fuge as acclimation after, until equilibrium is right)?

I'll post a few links below for you to read:

Disease eradication vs. Disease management (new)

This article expands upon the Ich eradication vs. Ich management thread I wrote. It takes other diseases - such as Velvet, Brook, Uronema, Flukes, Bacterial Infections - into consideration; and discusses the best strategies for preventing vs. managing all pathogens commonly found in a saltwater...

humble.fish

How To - Peroxide (H2O2) dosing for parasites in reef tank

***Current dosing recommendation for active outbreaks, using 3% hydrogen peroxide*** (a TLDR for people who just need to know how to get started) Week 1: 1mL/8g, 3x per day Week 2: 1mL/5g, 3x per day Week 3: 1mL/5g, 3x per day, plus overnight dosing. Continue the week 3 dosing regimen for a...

humble.fish

Hydrogen Peroxide bath

Hydrogen Peroxide bath (updated 1-31-23) What It Treats: Provides temporary relief for Marine Velvet Disease and Brooklynella. After a 30 minute H2O2 bath, the fish should be transferred into a Quarantine Tank (QT) for followup treatment. How To Treat: (The following is needed) 3% Hydrogen...

humble.fish