The chemistry of acclimation

[Baldguy]

Everything considered what is the best way to acclimate fish? Reason I ask is all these years I've drip acclimated for 1 or 2 hours then floated for 15 minutes to equalize temp then into the tank. Reefcleaners wants absolutely no acclimation other than floating for temp because of ammonia and ph levels. https://www.reefcleaners.org/acclimation I've read of others that suggest very little acclimation. Often the fish have a little shock after shipping so I don't really know if it's because of my acclimation procedure or just because of shipping stress. Got two wrasses in today from DD and both are experiencing some shock. Would hate to think it's because of me. So what say you? Thanks

 

[drstratton]

I don't think that Reef Cleaners are talking about acclimating fish in this manner. Just the snails and crabs that they sell on their site.

"You may find this to be different than the acclimation procedure you are used to carrying out. The reason we ask our customers to use this procedure is because our snails and crabs live intertidally, and can handle swings in ph/salinity without a problem."

 

[Baldguy]

I agree but their comments about ammonia and ph do pertain to fish and others do go with minimal acclamation for fish.

 

[drstratton]

I agree but their comments about ammonia and ph do pertain to fish and others do go with minimal acclamation for fish.

Gotcha! I would also like to hear from someone who knows more than I do, chime in on this!

 

[Randy Holmes-Farley Verified Community Expert]

Yes, this is a debated topic.

IMO, for fish and others that have been in a bag overnight or longer, it is a lot better to make the QT tank match the bag salinity than to acclimate the fish by dripping. Even aerating alone can spike free ammonia.

If you have a fish in a bag that must go into water that doesn't match salinity, it can be tricky to decide which is best: a salinity jump, or a temporary ammonia spike. The actual answer may depend on the salinity difference and the likely level of ammomia based on what was in the bag and for how long.

FWIW, one could also acclimate with low pH water of the same temp and salinity as the main tank (perhaps by adding a little soda water to the tank water used for acclimation). That would eliminate the free ammonia spike.

 

[Baldguy]

Thank you Randy. I did check the DD water and it matched my own for salinity. Wish I had just floated to equalize temp and put in the tank. Next time I will.

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, we had a Reef Chemistry Question of the day on this topic:

https://www.reef2reef.com/threads/reef-chemistry-question-of-the-day-12.173979/

 

[Cory]

I always just scoop the fish out with my hand and directly into the tank. (Hand to minimize tank water entering the tank and its softer than a fish net) Which may be controversial to some but its always worked for me, ive never had a fish loss due to chemistry differences, or disease in 10 years. Ive had fish get disease but thats from my tanks water chemistry being off perpetuating and thus lowering the fishes defensive system. It was always one of the group might get sick, but i treat them with a gentle h202 bath which kills ich and other parasites or bacterial infection. This was rare though.

I dont worry about temperature differences because reefs can have "cold pockets" that change rapidly. Besides most fish might be in water thats much colder than they should be in.

My reasoning is ammonia is the big fish killer. So i dont acclimate a fish in 1/3 a gallon of water. Always seemed ridiculous to keep a fish in that little bag of water. Its like swimming in a recently used toilet.

 

[Baldguy]

I always just scoop the fish out with my hand and directly into the tank. (Hand to minimize tank water entering the tank and its softer than a fish net) Which may be controversial to some but its always worked for me, ive never had a fish loss due to chemistry differences, or disease in 10 years. Ive had fish get disease but thats from my tanks water chemistry being off perpetuating and thus lowering the fishes defensive system. It was always one of the group might get sick, but i treat them with a gentle h202 bath which kills ich and other parasites or bacterial infection. This was rare though.

I dont worry about temperature differences because reefs can have "cold pockets" that change rapidly. Besides most fish might be in water thats much colder than they should be in.

My reasoning is ammonia is the big fish killer. So i dont acclimate a fish in 1/3 a gallon of water. Always seemed ridiculous to keep a fish in that little bag of water. Its like swimming in a recently used toilet.

Every bit of that makes sense. I also use my hand as the fishes slime coat is not rubbed off as can happen with a net. I do wonder why most if not all of the online fish sellers want us to drip acclimate for an hour or more. LA/DD advises an hour. I'm beginning to think I've lost fish because of the ammonia after dripping for an hour or more.

What do you do when salinity is different? I keep my tank at 1.025 and some sellers keep there stock at 1.020 or so. Will the sudden salinity change harm the fish more than the ammonia?

 

[Cory]

Every bit of that makes sense. I also use my hand as the fishes slime coat is not rubbed off as can happen with a net. I do wonder why most if not all of the online fish sellers want us to drip acclimate for an hour or more. LA/DD advises an hour. I'm beginning to think I've lost fish because of the ammonia after dripping for an hour or more.

What do you do when salinity is different? I keep my tank at 1.025 and some sellers keep there stock at 1.020 or so. Will the sudden salinity change harm the fish more than the ammonia?

Im not sure why they say drip acclimate. Possibly business related as they can ask did you drip acclimate the fish? If you say no, sorry no refund. Perhaps they just dont know.

As far as salinity, that might be a concern to me. Id probably drip acclimate deep water fish with a dropbor two of ammonia remover in the bag. Deep water fish wouldnt be exsposed to rapid salinity changed so much due to rain storms as say a shallow water species might. Jawfish?

 

[Myka]

I have a QT, and I keep the salinity of the tank the same as the main LFS that I shop at. I float the bag to match temperature, then I scoop the fish with my hand and into the QT. I don't drip.

If I buy fish at the LFS that are still in their original bag water from a wholesaler (Canadian, US, or overseas) or I order fish that are shipped to me, then I will check pH of the bag water, drop the pH in my QT so it's within 0.2, and otherwise do the same as above (including matching salinity). The pH of the QT is usually up to the usual 7.8-8.0 in 4-6 hours. I let salinity increase by topping up with saltwater instead of RO.

 

[Randy Holmes-Farley Verified Community Expert]

I have a QT, and I keep the salinity of the tank the same as the main LFS that I shop at. I float the bag to match temperature, then I scoop the fish with my hand and into the QT. I don't drip.
.

IMO, that is a perfect way to acclimate from shops that have low salinity.

Then you can slowly raise the Q tank over time to match the display (which I expect you do).

 

[Myka]

IMO, that is a perfect way to acclimate from shops that have low salinity.

Then you can slowly raise the Q tank over time to match the display (which I expect you do).

Yes, I top up the QT with saltwater until the salinity matches the display.

 

[Lionfish Lair]

We were just chatting about this. The pictures I've included in this thread, is why I do not drip acclimate. Best Way to De-bag Fish

It's also said they really are not acclimating in the amount of time we give them. It's not measured in minutes or hours, but days and weeks.

 

[Baldguy]

Thanks for that link Renee. Lots of good info. I've come to believe Ammonia is a much bigger problem than acclimating for minor differences in salinity and other things (ph).

As I stated before, I wonder why fish sellers that ship overnight do not recognize this problem. You'd think they'd have an interest in their fish living especially since they are covering losses in most cases.

Anyway, thanks for everyones thoughts and experiences. I'll be floating for temp and then adding to tank.

 

[atoll]

What's the longest period a fish will be in a little bag of water? Well in the case of the UK almost certainly while it's being shipped from the shipper to the wholesalers or shop. I know many shops but not one will drop acclimatise fish. The most used method of acclimatisation is to open the bag after floating to equalise temperature and using the bag scoop it under the holding or display tanks water. This will happen any number of times before the fish is released usually after around an hour. I do similar but discard most of the water in the bag rather than add it. I have never had a problem in 30 years acclimatising fish this way.

 

[Rhodophyta]

When fish are shipped long distances, say from Singapore to New York City, the fish are excreting both ammonia and carbon dioxide. The CO2 reduces the pH, making the ammonia less toxic for a time. Chemicals that relax the fish such as MS-222 are probably also in the chemical cocktail the water has become. At the same time the fish are in total darkness for the hours or days from shipping origin to destination. This is a different situation from acclimation after a short trip in a clear plastic bag from the local pet shop to the home tanks where drip acclimation makes sense for those locally acquired fish.

When receiving long distance shipments try this. Darken the room where the boxes will be opened to as dim as it can be while the humans still have enough light to see clearly. Open the boxes and slightly open the lids, then gradually open them further. The shipper can tell you the salinity to target, but temperature and pH are going to change out side anyone's control. Some fish are toxic or have sharp spines or sharp teeth. So you should make an informed choice about bare hands or nets. Get the fish but not the shipping water into the prepared quarantine tanks. Skimmers and UV will keep oxygen in the water and maybe kill some pathogens. Depending on species and source, a treatment routine of medications may be desired.

 

[brandon429]

Randy would you highlight for me the mechanism of the aeration/ammonia jump im hungry for all details ammonia. im guessing it was the offgassing and ph climb amplifying whats potentially in the bag unoxidized?

 

[Randy Holmes-Farley Verified Community Expert]

Randy would you highlight for me the mechanism of the aeration/ammonia jump im hungry for all details ammonia. im guessing it was the offgassing and ph climb amplifying whats potentially in the bag unoxidized?

Sure. Total ammonia does not change due to aeration, and will, in fact, drop during drip acclimation.

But the low pH in the shipping bag due to extra CO2 in in shifts the ammonia species more into ammonium and less free NH3. The free NH3 crosses membranes much more easily and so is more toxic.

So when acclimating, the pH will generally be rising from CO2 leaving the bag water, and from higher pH tank water entering it. So the free ammonia increases, increasing toxicity, even though total ammonia may be stable or declining.

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, I detail these issues with respect to ammonia and pH here:

Ammonia and the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2007-02/rhf/index.php

from it:
Figure 1. The fraction of free ammonia (NH3) and ammonium ion (NH4+) present in seawater as a function of pH.

Ammonia and Ammonium as a Function of pH

The pKa of ammonium in seawater is about 9.3 (some references state 9.5, with the difference possibly relating to the different pH scales sometimes used for seawater and freshwater).2 That pKa means that at pH 9.3 the water has equal concentrations of ammonium and ammonia. At pH values below this level, as is always the case in reef aquaria, ammonium predominates. Figure 1 shows a plot of the relative fractions of ammonia and ammonium as a function of pH in seawater. At pH 8.2 only about 7% of the ammonia is present as free ammonia, with 93% present as ammonium.

Because many authors attribute ammonia's toxicity primarily to free ammonia (whether this is correct or not, see below), Figure 2 shows an expanded view of Figure 1 for the free ammonia concentration over the pH range of usual interest in reef aquaria. The amount of free ammonia present at pH 7.8 is about one-fourth the amount present at pH 8.5.

Figure 2.The fraction of free ammonia (NH3) present in seawater as a function of pH over the range of most interest to reef aquarists. This figure reproduces Figure 1 on an expanded scale.

Reef aquarists also are often interested in pH values below those typically present in actual reef aquaria. A shipping bag containing fish, for example, often drops substantially in pH over the course of hours to days, as a result of expelled carbon dioxide. That change in pH can convert even more of the free ammonia to ammonium, and Figure 3 shows the fractions of ammonia and ammonium on a log scale, making it clear that the free ammonia continues to drop in concentration as the pH drops, even when it is already present as a very small fraction.

Figure 3.The fraction of free ammonia (NH3) and ammonium ion (NH4+) present in seawater as a function of pH. This figure shows the fraction on a log scale over a wider pH range than Figure 1.