Freshwater Dip

[trevorhiller]

I’m in the midst of QTing a flame hawk fish and dosing copper safe for the first time so I’ve been trying to read as much as I can on the QT process and fish treatment and disease. I was reading about freshwater dips and it kind of blows my mind. I’ve always read you need to slowly acclimate a fish to the pH and salinity of your tank when adding them.

How do fish tolerate and survive a freshwater dip and then going straight back into higher salinity with no issue, but we drip acclimate fish for salinity. This seems very contradictory and I’m just curious on why this is “ok”/why we drip acclimate.

 

[blaxsun]

Well, the freshwater dip is usually only for a few minutes whereas the acclimation is for 35-45 minutes (or longer).

 

[vetteguy53081]

I’m in the midst of QTing a flame hawk fish and dosing copper safe for the first time so I’ve been trying to read as much as I can on the QT process and fish treatment and disease. I was reading about freshwater dips and it kind of blows my mind. I’ve always read you need to slowly acclimate a fish to the pH and salinity of your tank when adding them.

How do fish tolerate and survive a freshwater dip and then going straight back into higher salinity with no issue, but we drip acclimate fish for salinity. This seems very contradictory and I’m just curious on why this is “ok”/why we drip acclimate.

It’s a 5 minute process and erraficates mainly flukes and worms, and copper is the quarantine protocol for a full 30 days at therapeutic level 2.25-2.5 monitored with a reliable copper test kit such as Hanna brand

 

[LiamPM]

You have a point - And one ive asked about a few times previously too.

If we have to acclimate a fish into our tanks salinity over a period of 30 minutes or so because a change in salinity is so dangerous then why is a freshwater dip not considered dangerous in this term too.

An odd one for sure - I still freshwater dip when needed and still acclimate over 30 minutes or so for safety but its definitely a good talking point.

 

[Jay Hemdal]

First thing, marine fish are very sensitive to salinity rises, but drops are not as much of a problem. Second, it has to do with kidney function and the need for that organ to adapt to different salinity. The dip, being ~5 minutes long, doesn't invoke much of a change. Kind of like how you can hold your breath for 3 minutes, but not 30.

Remember though - FW dips are not a comprehensive treatment, they always leave a percentage of parasites attached to the fish. I use them as a diagnostic tool, I then look at the dip water under a microscope and scan it for parasites. I sometimes use them to buy some time before another treatment can be started....

Jay

 

[MnFish1]

In addition to what Jay said changes in salinity can damage the gills, change the chemical composition in the blood - which can cause brain swelling, etc. It takes time for those changes to occur - but it's also why one of the signs to stop a freshwater dip is if the fish looks 'comatose'. If it is damaging the cells on the parasite - it probably also to a slight degree damaging the cells of the fish temporarily. I'm personally not a big believer in a FW dip except in dire situations (like velvet) or a quick check for Flukes, etc. When I see some people say 'I did 3 FW dips' I wonder how much damage is actually being done to the fish longer term.

 

[Reef.]

I think the premise of your question is wrong, that salinity is the only reason we Acclimatise fish.

Salinity is important but so is ph and temp.

You are also meant to match the ph and temp of a fresh water dip, my guess is that these two parameters are just as important when acclimating a fish, if not more important than the salinity.

 

[MnFish1]

I think the premise of your question is wrong, that salinity is the only reason we Acclimatise fish.

Salinity is important but so is ph and temp.

You are also meant to match the ph and temp of a fresh water dip, my guess is that these two parameters are just as important when acclimating a fish, if not more important than the salinity.

Temp yes - there are many people that do not match the pH in a Freshwater dip. The biggest change in taking a fish from saltwater to freshwater is the salinity. When acclimating a fish - the salinity is extremely important. In fact, many fish deaths relate to problems where an LFS keeps their salinity at 1.020 - and people "acclimate" their fish over 30 minutes - and the fish have problems. I.e. you can adjust pH and Temp over 1/2 hour. You cannot adjust salinity the same way depending on the difference

 

[Rawsreef]

Kind of my train of thought on the situation as well. I always felt like it would be brutal on the fish, a fish that we already suspect are not 100% healthy. (chasing them around with the net to transfer probably wont help much either)

But what Jay said makes sense to me.

I could see it being that, as long as the pH, and temp are matching; The actual FW dip may not be as harsh on the fish as it may seem.

 

[trevorhiller]

You have a point - And one ive asked about a few times previously too.

If we have to acclimate a fish into our tanks salinity over a period of 30 minutes or so because a change in salinity is so dangerous then why is a freshwater dip not considered dangerous in this term too.

An odd one for sure - I still freshwater dip when needed and still acclimate over 30 minutes or so for safety but its definitely a good talking point.

This is what I was getting it. At first glance, it first glance, it seems like the rapid change in salinity isn't an issue if they can withstand 35 ppt --> 0 ppt --> 35 ppt all in 5 mins. Yet people will cite an adjustment of a few ppt over 30 mins is "too quick" and "killed the fish."

First thing, marine fish are very sensitive to salinity rises, but drops are not as much of a problem. Second, it has to do with kidney function and the need for that organ to adapt to different salinity. The dip, being ~5 minutes long, doesn't invoke much of a change. Kind of like how you can hold your breath for 3 minutes, but not 30.

Remember though - FW dips are not a comprehensive treatment, they always leave a percentage of parasites attached to the fish. I use them as a diagnostic tool, I then look at the dip water under a microscope and scan it for parasites. I sometimes use them to buy some time before another treatment can be started....

Jay

Interesting. I still wonder about the movement back from 0 ppt to ~35 ppt instantly. This seems like it would be much more dramatic of a change on fish than a 3-5 ppt increase "too quickly" during acclimation that people often cite as a cause of fish loss during the process.

I think the premise of your question is wrong, that salinity is the only reason we Acclimatise fish.
Salinity is important but so is ph and temp.

You are also meant to match the ph and temp of a fresh water dip, my guess is that these two parameters are just as important when acclimating a fish, if not more important than the salinity.

No, I do realize that, what I'm getting at though is are rapid salinity swings actually a cause of death during fish acclimation as people often claim. We often say that fish can't tolerate temp changes, salinity changes, etc. But I'm sort of skeptical since there are spots in the ocean with different temperatures (thermoclines) that fish seem to swim through without any adverse effect. Then seeing fish go through rapid salinity changes during freshwater dip has me questioning that too. It makes me wonder about the acclimation process.

Same thing with inverts, Reef Cleaners suggests floating them and then simply dropping them in. Others will state that are very delicate and need acclimated. I've used their method and it works fine. No pH/salinity acclimation and no issues.

I'm just a skeptical person and like to know how things work; this was just a thought experiment that popped into my head after doing some reading for fun. There is a lot of regurgitated information in this hobby without a ton of scientific information to back it.

 

[MnFish1]

This is what I was getting it. At first glance, it first glance, it seems like the rapid change in salinity isn't an issue if they can withstand 35 ppt --> 0 ppt --> 35 ppt all in 5 mins. Yet people will cite an adjustment of a few ppt over 30 mins is "too quick" and "killed the fish."

Interesting. I still wonder about the movement back from 0 ppt to ~35 ppt instantly. This seems like it would be much more dramatic of a change on fish than a 3-5 ppt increase "too quickly" during acclimation that people often cite as a cause of fish loss during the process.

No, I do realize that, what I'm getting at though is are rapid salinity swings actually a cause of death during fish acclimation as people often claim. We often say that fish can't tolerate temp changes, salinity changes, etc. But I'm sort of skeptical since there are spots in the ocean with different temperatures (thermoclines) that fish seem to swim through without any adverse effect. Then seeing fish go through rapid salinity changes during freshwater dip has me questioning that too. It makes me wonder about the acclimation process.

Same thing with inverts, Reef Cleaners suggests floating them and then simply dropping them in. Others will state that are very delicate and need acclimated. I've used their method and it works fine. No pH/salinity acclimation and no issues.

I'm just a skeptical person and like to know how things work; this was just a thought experiment that popped into my head after doing some reading for fun. There is a lot of regurgitated information in this hobby without a ton of scientific information to back it.

The analogy would be if you touched your finger to the stove for 1/2 second it might get a little red. If you left it on the stove for 30 minutes it would be damaged. A quick salinity change and reversal is less harmful than a change in specific gravity from 1.019 to 1.025 which is then left at 1.025. FYI that is a Chan salinity of about 10

 

[alton]

At one time San Antonio had an LFS that only sold quarantined fish. The owner who also took care of my bosses aquariums told me to always FW dip a fish. FW dipping a $30 Regal Tang not so Bad, a $400 Redsea Juvenile Mis-bared Regal angel is tough. I have never lost a fish during or after a FW dip, I have lost fish that I did not dip. I have had a Copperband Butterfly for 13 years before it perished. A Flame angel for 10+ years that I lost when I didn't leave a newer fish in QT for a long enough time that I purchased from a place that I thought was bullet proof before adding to the display. Matching PH and Temp is Key. Great advice coming from some great individuals on here, just keep asking questions.

 

[rapmelodies]

At one time San Antonio had an LFS that only sold quarantined fish. The owner who also took care of my bosses aquariums told me to always FW dip a fish. FW dipping a $30 Regal Tang not so Bad, a $400 Redsea Juvenile Mis-bared Regal angel is tough. I have never lost a fish during or after a FW dip, I have lost fish that I did not dip. I have had a Copperband Butterfly for 13 years before it perished. A Flame angel for 10+ years that I lost when I didn't leave a newer fish in QT for a long enough time that I purchased from a place that I thought was bullet proof before adding to the display. Matching PH and Temp is Key. Great advice coming from some great individuals on here, just keep asking questions.

Matched pH and temp and fish didn't make it. I was only suspecting flukes. Fish looking amazing but might have been breathing a bit fast before I did the dip.

 

[trevorhiller]

Matched pH and temp and fish didn't make it. I was only suspecting flukes. Fish looking amazing but might have been breathing a bit fast before I did the dip.

Sorry to hear that, such a terrible feeling.

I’m expecting my second replacement Tomini tang this week and I’m terrified to acclimate it because the first died just shy of two weeks in and last one died during acclimation.

 

[rapmelodies]

Sorry to hear that, such a terrible feeling.

I’m expecting my second replacement Tomini tang this week and I’m terrified to acclimate it because the first died just shy of two weeks in and last one died during acclimation.

Yea I haven't been this mad about a fish loss in over a decade. But I am planning on lots of expensive fish in a big tank I am working on setting up. So I either need to figure out how to be proficient in quarantine or buy fish at twice the price for someome else to do the quarantine process.

 

[gbroadbridge]

Matched pH and temp and fish didn't make it. I was only suspecting flukes. Fish looking amazing but might have been breathing a bit fast before I did the dip.

The dip did not kill the fish.

Something else did.

Just netting a fish can cause internal damage which is fatal in many cases.

Just crashing into the wall or a rock can cause death.

 

[rapmelodies]

The dip did not kill the fish.

Something else did.

Just netting a fish can cause internal damage which is fatal in many cases.

Just crashing into the wall or a rock can cause death.

 

[rapmelodies]

I wish I knew what could have caused it.

 

[trevorhiller]

Yea I haven't been this mad about a fish loss in over a decade. But I am planning on lots of expensive fish in a big tank I am working on setting up. So I either need to figure out how to be proficient in quarantine or buy fish at twice the price for someome else to do the quarantine process.

I hear you, both of mine I paid for QT too and they still didn’t survive.

I’m trying my own QT now on some fish because buying from petco locally seems to be less stressful then I can wipe out the potential diseases myself.

 

[Jay Hemdal]

I hear you, both of mine I paid for QT too and they still didn’t survive.

I’m trying my own QT now on some fish because buying from petco locally seems to be less stressful then I can wipe out the potential diseases myself.

Here is a link to our current quarantine protocol:

Current Quarantine Protocol

2023 Quarantine Procedures Jay Hemdal David Scarborough Protozoans (Cryptocaryon/ich, Amyloodinium/velvet) and Metazoan trematodes/flukes are by far the most common parasites found on newly acquired fish. A carefully managed quarantine process can effectively eliminate these parasites before...

www.reef2reef.com

Jay