Preis Carely gill and intestinal care for fish
| Capacity | Price | Price per L | vs 250 ml |
|---|---|---|---|
| 250 ml | $23.00 | $92.00 | — |
| 1 L | $80.00 | $80.00 | −13 % |
This treatment, made from plant-based raw materials, acts on the gills and digestive tract of aquarium fish, in freshwater and in seawater alike.
It is added to the water following a 9-day protocol, or mixed into the food for 3 days, particularly for discus and newly imported fish.
The summary
- In the water: 15 ml per 100 litres, on days 1, 2, 8 and 9.
- In the food: 10 ml in a tablespoon, twice a day, for 3 days in a row.
- What it is safe for: plants, corals and invertebrates.
- To remove from the filter: activated carbon, ion-exchange resins and zeolites.
- Or salt instead?: the choice depends on what you observe in the fish.
- Shipping: bottle sent by tracked parcel from France.
Care for the gills and digestive tract, in the water or in the food
This treatment targets the two organs through which most of a fish's exchanges with its environment take place: the gills, through which oxygen passes, and the digestive tract, through which food passes. Preis Carely is made from plant-based raw materials, can be used in freshwater and seawater, and is safe for plants, corals and invertebrates. You can therefore pour it straight into your main aquarium, without setting up a hospital tank and without moving a fish that is already weakened.
📆 A 9-day protocol
The in-water protocol is not given all in one go. You pour in 15 ml per 100 litres on the first day, the same dose on the second, then you add nothing for 5 days. The eighth and ninth days repeat the same dose, and this repeat belongs to the same treatment. Calculate your dose on the actual volume of water in your tank, with decor and substrate deducted, and note down the four dates before you begin.
Days 1 and 2
Pour every 100 litres of water, pour in 15 ml, on 2 days in a row.
Days 3 to 7
The product stays in the water with no further dosing for 5 days.
Days 8 and 9
Dose another 15 ml per 100 litres, 2 days running.
Measure the ammonium and nitrite before treating
A fish breathing rapidly at the surface may be suffering from gill problems, but also from water loaded with ammonia or nitrite. So carry out a nitrite drop test and an ammonium drop test before the first day of the protocol. If either one is positive, a water change takes priority over the treatment, and you avoid treating a symptom whose cause remains in the tank.
Remove carbon, resins and zeolites from the filter
Remove the activated carbon, ion-exchange resins and zeolites before you begin, as these three media capture the product before it reaches the fish. The protein skimmer, the UV and the biological filtration or mechanical filtration stay in service throughout the protocol. The product is for use in ornamental fish aquariums, freshwater or marine, and never on a system whose fish are intended for consumption.
🍽️ The food route
The second route goes through the food: you let 10 ml soak into about a tablespoon of food for a few minutes, then feed it, twice a day, for 3 days in a row. It concentrates the action on the digestive tract instead of diluting it throughout the tank, which makes it worthwhile when a fish is still eating but losing weight. It assumes your fish is feeding, since a fish that refuses all food can only be reached through the water: so watch a full feed before choosing your route. If your fish is eating normally and shows no symptoms, use a maintenance tonic rather than a treatment.
🐠 The fish concerned
The treatment is intended for ornamental fish, and in particular for discus, Lake Malawi cichlids and newly acquired or imported fish, which transport and the change of water leave weakened. For these, as for your most sensitive fish, the two routes can be combined: the in-water protocol for the gills, and the soaked food for the digestive tract. However, give new arrivals time to settle into stable water before you begin.
🧴 250 ml or 1 litre
The full in-water protocol uses 60 ml per 100 litres, that is, 4 days of dosing at 15 ml. If your tank holds 240 actual litres, allow 36 ml per dosing day and 144 ml for the whole course, which the 250 ml bottle covers with some to spare. That same bottle is enough for a full protocol up to about 400 litres, whereas the food route uses only 60 ml per 3-day course. The 1 litre bottle is worthwhile above 400 litres, across several tanks, or for a breeder who regularly treats new arrivals: it covers a full protocol for about 1,600 litres.
Technical specifications
The essentials
- What the treatment targets
- Gills and digestive tract
- Composition
- Plant-based raw materials
Both protocols
- In the water
- 15 ml per 100 LOn days 1, 2, 8 and 9, without adding anything in between.
- In the food
- 10 ml per tablespoonLeave to soak in for a few minutes, twice a day, for 3 days in a row.
Compatibility
- What stays in place
- Plants, corals, invertebrates
- Waters concerned
- Freshwater and saltwater
To budget for separately
- Media to remove
- Activated carbon, resins, zeolites
- Water monitoring
- A nitrite test
In the box
- 1 bottle of 250 ml or 1 L, depending on the size chosen
Protocols, composition, fish concerned and filtration instructions: manufacturer's documentation, recorded on 20/09/2026 and 11/10/2026.
Two bottles for two different situations
One is for a fish that is unwell, the other for water that has just been changed. Look at the fish first.
| What the product is aimed at | For a fish that breathes poorly or is losing weight | For a tank that is starting up or having its water changed | Directions for use | Can be given in the food | Added with every water change | Be careful with live plants | Activated carbon to be removed during use | Price | |
|---|---|---|---|---|---|---|---|---|---|
| Recommended Preis Carely gill and intestinal care forYour choice | The fish's gills and intestine | Yes | No | 15 ml per 100 L on days 1, 2, 8 and 9 | Yes | No | No | Yes | $23.00 |
| API aquarium salt for freshwater fishYour choice | Adding electrolytes to the water | No | Yes | 1 heaped tablespoon per 20 L | No | Yes | Yes | No | $36.00 |
Protocols, compositions and warnings taken on 20/09/2026 and 11/10/2026 from the Preis-Aquaristik documentation and from the product sheet on the official API Fishcare website.
Help choosing
What you observe at home
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It is not a guaranteed delivery date: public holidays, peak periods, customs or a carrier delay can extend it. The exact amount, in your currency, is worked out in the cart once your address is entered.
Shipped as a tracked parcel from France, which can be combined at no extra cost with the rest of your order. The exact charges and delivery times are shown in the basket once the address has been entered. Outside the European Union, import duties and taxes are payable by the recipient.
Frequently asked questions
8 questions
6 key questions, 8 in the detailed view
How much for one day of dosing
Enter the actual volume of your aquarium, with the decor deducted.
per dosing day, at a dose of 15 ml per 100 litres
Protocol taken on 20 September 2026 from the Preis-Aquaristik instruction leaflet.
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