How to Start and What You Need to Set Up Your Jellyfish Tank
If you’ve been gifted or purchased a jellyfish tank, we’ll explain step-by-step how to set it up. If you still have questions, feel free to email us at info@medusea.es we’ll be happy to help. All the products described here are available in our online store: medusea.es/shop. These are carefully selected items from the vast market offering, tested and proven to be the best for jellyfish care.
What We Have:
- Jellyfish tank.
- Bio-balls (included with the tank)
- Hydrometer/thermometer (included with model O16, not with AquaJelly)
- Siphon with silicone tubing and a rigid tube (included)
- Feeding pipette (included)
- Sponge functioning as a mechanical filter
- LED lights and remote
What We Need:
- Distilled or reverse osmosis water
- Marine salt for aquariums – Marine PRO Salt
- Starter for the biological filter (bacteria)
- Conditioner for maintenance (neutralizes NH₃ spikes, heavy metals, chlorine). Prime by SEACHEM.
- Chemipure blue nano. (22g pouch) – Mix of activated carbon and resins; absorbs nitrogen compounds, phosphates, clarifies water — or use PURIGEN
- Live food (zooplankton) or an Artemia hatcher to grow your own
- Dry jellyfish food or Coralific Delite
- Tests pH, NH3, NO2, NO3 of SALIFERT or the MARINELABS parameter kit
- Jellyfish
- Soft sponge or cloth (non-abrasive) to clean algae film off acryli
These are our essential recommendations, but you’ll find more helpful items in our store to maintain stability.
Jellyfish Tank Setup
Start by unpacking your tank and checking that all kit components are present and in good condition. If there’s any issue, contact your supplier. Always follow your tank model’s instructions. The following is a general guide:
- Rinse the bio-balls with tap water to remove dust and place them in the designated compartment.
- Insert the sponge in the correct position.
- Connect the pump to the intake hose and place it in its compartment.
- Fill the tank with distilled or RO water — NEVER TAP WATER.
- Weigh out the correct amount of salt — typically 30g per liter:
- 20L → 600g
- 16L → 480g
- 10L → 300g
- 7L → 210g
- 15L → 450g
- Add salt to the tank.
- Turn on the pump — it may be noisy at first; gently shake it to release trapped air.
- Let the salt dissolve completely; after 24 hours, check salinity with a hydrometer and adjust if needed.
- Add the ammonium salts vial included in the MEDUSEA QUICK START GUIDE to feed the bacteria.
- Add a bacteria starter based on tank volume. Follow manufacturer instructions:
- STABILITY: 2 ml daily for 7 days
- FRITZ ZYME 9: half the bottle now, the rest 3 days later (refrigerate once opened)
- Wait 2 Weeks
- Then test water parameters. You may encounter different cases:
- if NH3=0; NO2=0 and NO3>40ppm do a 15% water change — your tank is ready.
- if NH3>0ppm (da positivo); NO2>0ppm and NO3=0. wait another week and retest.
- if NH=0 and NO2>0ppm, wait until NO₂ = 0
- ifNH3=0, NO2=0 and NO3>0 your filter is ready. Do a 20–40% water change with pre-mixed saltwater to reduce excess NO₃. Now you can order your jellyfish!
This process takes time but is essential for keeping your jellyfish healthy and stress-free. Patience is key. For a deeper understanding of the nitrogen cycle, see our post “Cycling Your Aquarium.”
Make sure your biological filter is fully cycled before introducing jellyfish!
Jellyfish Acclimation
Once your jellyfish arrive, they need to be acclimated. There are several methods:
- Method 1:Transfer jellyfish to an external container with the water from their shipping bag.
Add 1–2 scoops of tank water every 10 minutes for about an hour. - Method 2 (if space allows): Float the sealed bag in the aquarium to match temperatures.
Slowly add tank water to the bag to equalize parameters.
Introducing Jellyfish into the Tank
Once acclimated, gently place them in the tank using the provided ladle. Avoid trapping bubbles inside them.
- Have bubbles inside → gently remove them by hand or pipette.
- Sink to the bottom the shipping water may be denser. They’ll adapt with time. Temporarily increase flow to help.
- Float → the shipping water may be less dense. Check salinity. If too high, slowly dilute with lower-salinity water. Never pour distilled water directly on jellyfish or bio-balls.
Feed only small amounts and observe: if their stomachs change color, they’re eating. You can feed a second time if needed.
Use the provided doser:dissolve a portion of food in tank water, mix, then feed.
Maintenance
Once acclimated, gently place them in the tank using the provided ladle. Avoid trapping bubbles inside them.
Place a pre-rinsed Chemipure pouch in the pump compartment once the tank is stable — it helps absorb nitrogen compounds and clarify water.
Alternatively, use PURIGEN resins — reusable and effective at removing toxins.
If you still have questions, check our FAQ section or download the Jellyfish Care & Maintenance Manual.
DONE! Your jellyfish tank is set up and running — now enjoy it!