In Davis’ example, the treatment referred to, was the application of a series of salt dips, coupled with in tank temperatures of 35oC, large daily water changes using fresh conditioned water, and scrupulous tank hygiene. Below, I list a couple of methods that I have used and that have worked for me and others I have visited. If you choose to use the examples – do so with great care – remember, the onus is on you to make judgements regarding appropriate treatment and the current condition and status of your fish and tanks – if you are unsure, nervous or need help, please ask, or seek professional advice.
Discus Salt Dip Methodology
Type of salt to use:
The type of salt used should be non-iodized and contain no ‘free flow’ or other additives (e.g. no iodine or sodium ferrocyanide etc. I have used ‘Freshwater Aquarium Salt’, rock salt and sea salt. If purchasing non-aquarium salt please read the packaging carefully as current trends show an increase in the use of additives even in natural products such as rock salt (UK).
If new to Salt Dipping
If new to dipping fish a good place to start would be with a 1.5-2% salt solution; for more experienced users I would suggest you start with a 3% solution immediately. The solution should be made up in a clean bucket or spare (fishless) tank. Whilst it is preferable to weigh out the correct amount of salt e.g. for a 2% solution one would use 20g of salt per litre of water, the following approximate measure are given for the sake of simplicity.
1 TABLESPOON of salt approximates to 15grams.
Therefore 1 TABLESPOON of salt per litre of water equates to a 1.5% solution
Worked examples (See Table 1 for other strengths):
· If your bucket/tank contains 10 litres of water you would add 13 tablespoons of salt to get an approximate 2% salt solution
· Or - If you place 3 US gallons of water in a 5 gallon bucket you would add 14½ tablespoons of salt - to get an approximate 2% solution.
And so on
· It is important to ensure that the salt is fully dissolved before placing the fish in the bucket/tank and that the water temperature matches the tank from which the fish are taken.
As you will need to multi-dip throughout the day, place a heater in the tank, if you do not want to have to remake new salt solution each time; personally I make a fresh solution for each dip.
Before you place the fish in the solution please remember that:
· The length of time that you can leave discus in the solution varies greatly from a few seconds to 30 minutes
o 5 minutes would be a reasonable average
· The time they tolerate the dip DECREASES with the number of dips performed in a 24 hour period
· The fish MUST NOT be left unattended
· During the treatment your fish may show some interesting discolouration, do not worry this is short term.
Place the fish into the solution as quickly and as carefully as possible - then observe closely.
Initially, the respiration of the fish will increase substantially, 120 gill beats per minute is not uncommon. At some point, the fish will keel over on its side - and it is at this point that the novice should remove the fish and return it to its tank. If you are confident and experienced in dipping you may want to extend the time that the fish is exposed to the saline solution - I have found it effective to leave the fish in the solution until the gill beats have slowed to around 20 bpm - irrespective of whether the fish has keeled over or not.
Once the fish are returned to their tank they should within a few minutes regain their composure. If they appear to be in difficulty, the fish can be supported using your hands and then gently pulled backwards through the water at a slow pace - so that water is forced over the gills.
I have dipped 5 times a day for up to 7 days and there has been no lasting negative effect. It is important that the dips continue until all visible signs of infection are gone.
Salt Solution
0.1%
0.2%
0.3%
1%
2%
3%
10
Litres
1
2
3
100
200
300
salt
in grams
10
US Gallons
3.8
7.6
11.4
379
757
1136
10
Imperial Gallons
4.6
9.1
13.6
455
909
1364
TABLE 1A
Salt Solution
0.1%
0.2%
0.3%
1%
2%
3%
10
Litres
0.07
0.13
0.2
6.7
13
20
salt
in table-spoons
10
US Gallons
0.25
0.5
0.76
25
50
75.7
10
Imperial Gallons
0.3
0.61
0.91
30
61
90.9
TABLE 1B
Tables 1 A & B give approximate figures for various salt solution concentrations. It must be remembered that Table B are coarse approximations only.
Important Note:
In regards to salt dipping it may be argued that returning the dipped fish to the tank from which it came is pointless – this is not the case. Ideally we would want to return the fish to a tank which had been sterilised and which contained 100% fresh (but conditioned) water, with a matured filter. It is important to remember here, that all we are doing is ‘knocking back’ the population of a ubiquitous organism and promoting the production of copious amounts of slime layer in order that the fish immune system can regain control and management of the problem. If we must return the fish to the same tank etc. then large water changes with conditioned water, scrupulous tank hygiene and the addition of salt at a rate of 2 table spoons per 10 gallons (assuming that the tank does not contain delicate plants or salt intolerant species) can work wonders – in conjunction with correct salt dipping.
Whilst I personally prefer the use of salt - it should not be forgotten that there are several alternatives. In relation to discus, various combinations of: potassium permanganate, formalin, temperature, hydrogen peroxide, acetic acid, large water changes, and so on, have been used to help CONTROL the external infection - with the likelihood of success being dependent on the virulence of the strain involved. For the sake of balance I will summarise the use of potassium permanganate (as an insitu bath [not a dip]).
