Juvenile Green Spotted Puffer - Help Please

[Laser]

I believe I have a juvenile GSP, as he is only 1.5 inches long. I got him at Walmart (I know please spare me of the lectures) so I am assuming he was kept in freshwater. I brought him home today and acclimated him to my empty 20g but it is currently freshwater.

This will be my first shot a brackish water tank. I have already read that they begin their lives in freshwater but eventually will end up in full marine water. I also understand that the 20g may not be large enough for him in the future

The article that I read said to shoot for a gravity of 1.006 for young puffers. I have no idea how to do that, but I intend to purchase the marine salt and hydrometer tomorrow. I assume that I will want to gradually increase the salinity with my weekly water changes. I'm just trying to avoid mistakes so any help would be appreciated.

 

[Terrance]

There are 2 ways of setting up a proper home for your GSP: you can either start building a larger marine tank while having your GSP in freshwater or you can slowly acclimate him to low-end brackish water. My preference is to set up a marine tank since you end up saving money in the long-term. Both are very overwhelming methods, so I would understand if you would just want to keep your GSP in light-brackish water. IMO setting up a marine tank is pretty easy with a online research.

The 2 options above is based on the importance of weekly water changes since I believe its the most important factor to keeping a healthy GSP long-term (5+ years). In a ideal world, every would want to keep their GSP for 5+ years.

Since you want to keep your puffer in brackish water, please invest in a refractometer (hydrometer is too inaccurate IMO/IME), marine salt (such as instant ocean but not aquarium salt), a spare heater, water pump, tubes, and water container (such as trashcan). These supplies will help you set up a proper mixing station. Premix the water overnight before doing a water changes, and eventually you can hook the tubes to the pump and transfer your water from water container to the tank.

This is how you would do weekly water changes. Use the refractometer to measure the salinity, and try to keep the salinity constant. Don't let him fluctuate too often. Evaporation of the water is your enemy since it makes the salinity change. In my own marine tanks, I use an auto top off system (tunze) to have peace of mind. Keep your salinity around 1.003. Water changes are expensive.

Please ask questions. I think I have covered enough for your to keep a light brackish tank.

 

[Laser]

In your opinion what is the best situation for the puffer? Is 1.003 good enough for the puffer's life? Are GSP's just that adaptable that they can thrive in 1.003 - 1.02? I was going to aim for 1.006 slowly, but if you think 1.003 is good I'll go with that.

3 days ago in an attempt to raise the salinity I removed 50% of the water and replaced it with water that was 1.002. This should have made the water in the aquarium 1.001. Is this a proper method of increasing the salinity?

He seems to be doing fine so far. He had some torn fins from fighting with the other puffers in their tiny 5 gallon space, but they seemed to have healed already. Also, no rings on the stomach which is something I have read to look for.

 

[Terrance]

Long term health requires at least high end brackish water. Around 1.015 and up is a good target, but those water changes will get expensive if you go that route. With marine water, you can use a skimmer and grow macroalgae to prolong water changes to a monthly task. Low end brackish, such as 1.006 you mentioned is good but your puffer will not live as long as marine water, but its better than straight freshwater.

Its very easy to think of no harm done if you miss one week of water change. If it happens once then there is a high likelihood of it happening again. Those missed water changes add up quikly.

Your brackish water acclimation sounds fine.

 

[Laser]

Thanks, I appreciate all of your advice. In the future I hope to be able to start a marine tank for this guy, but for now I think I'm going to go the brackish water route.