Alan the Puffer Alan the Puffer
  • Just popping in
  • Just popping in
  • Joined: 16/2/2011 12:43
  • From Somerset
  • Group: Registered Users Basic Membership
  • Posts: 1
  • Posted on: 16/2/2011 12:51
fresh to brackish for a green spotted puffer #1
hi everyone,

i recently bought a green spotted puffer fish (alan) he is about 2 inches long and when i got him he was in freshwater at the shop. I was told that he will be best kept in fresh water and was shown a very large looking fellow who had lived his life in fresh water to prove it when i questioned them!

Naturally i have researched this and almost everyone recommends this little chap should be in brackish water an of course i want the best for him. So, my question is.....

How do i change his water that he is used to, to brackish? should i just pop him in the changed water or should i adjust the water gradually changing it to brackish? if so what is the best way to do this? and whats the best salt to use? i know these guys are very sensitive so my concern is that if i take him out of fresh water into brackish straight way it could be to much of a shock for him.?.

any advice on this would be very much appreciated xx
Fishlady Fishlady
  • Tropical Moderator
  • Tropical Moderator
  • Joined: 6/7/2010 19:26
  • From Worcestershire
  • Group: Caresheets Moderators FK Supporter Registered Users Image Admin Advisers
  • Posts: 13240
  • Posted on: 16/2/2011 13:58
Re: fresh to brackish for a green spotted puffer #2

You should use marine salt for this, and will need a hydrometer to measure the specific gravity and ensure you end up with the right level of salinity for the fish. I don't know what the right level for this fish is but would think there's information specific to your fish on the net.

If he's used to fresh water then the change to brackish should be done gradually. I'd advise mixing up a quantity of brackish water to the correct level of salinity and then using it to carry out partial water changes of 10% or so twice a week until you eventually hit the same level in the tank, when you can go back to a standard water change regime. Monitor ammonia, nitrite, and pH carefully during the changeover.
Re: fresh to brackish for a green spotted puffer #3
Brackish waters are tidal, and the salinity changes greatly on a daily basis. Don't alter the salinity suddenly, but on the other hand don't worry too much about the values. As long as there is some salt in the water the fish will be fine.
Critch Critch
  • Home away from home
  • Home away from home
  • Joined: 15/12/2008 22:22
  • From Lancashire
  • Group: Registered Users Basic Membership Deep End
  • Posts: 1093
  • Posted on: 17/2/2012 9:29
Re: fresh to brackish for a green spotted puffer #4
Fish actually handle salinity changes pretty well, Brackish water fish are designed to swim through various salinities.. imagine one swimming along a marsh and swimming into the flow of water from a freshwater stream coming into the marsh.. they adjust to it. Obviously the slower and easier the acclimation the less stress, and less stress is always good.

It's the bacteria in your filter that cannot handle the changes,

slowly increase the salinity .002 or less every week until you reach the desired, I suggest keeping GSPs in low-end brackish water when juvenile, up to 2" in a specific gravity, or SG of 1.005-10, at 2-4", medium BW (SG 1.010-15) and adult SW (SG 1.018-22). You must use marine salt. You will need a hydrometer/refractometer to measure the salinity.

You ask how do I know all this, well i currently keeP two dwarf puffers I plan on keeping i really wanted a gsp but don't have the space for the them at the moment,
They really are one of the most rewarding fish I have ever kept,

Knowledge is knowing that a tomato is a fruit, wisdom is knowing not to put it in a fruit salad!
I dont keep fish i keep water the fish are only there for decoration