cycling a brakish tank

[Gavin]

Hi Guys,
I will shortly be purchasing a 57 gallon tank to house three figure eight puffers, i have spoken to my LFS and they sell their puffers in fresh water, so i will have to cycle my tank in fresh water i will be converting (after the puffers have settled) the water to brackish if i do so will the water have a major fluctuation in PH and amonia (will it mini cycle) i dont want to stess the little critters.
Thanks for any replies,
Gavin. :)

[MonoSebaelover]

Is there anyway you can cycle your tank in brackish and set up a little 10 gallon quarentine and slowly adjust the Puffs to brackish in the 10. Because if you have fw then start adding salt it will recycle once you hit brackish b/c fw bacteria can't handle salt. Or is there a way you can pick out a couple of puffs you like at the store and ask them to hold them in the back and let them raise the salinity?

[Sharyl C]

You could cycle your tank at 10-15ppt and over about 3 days acclimate you puffers from FW to you tank water. If you keep them in a smaller tank (or even a 5 gallon bucket) on an airstone they will be fine, assuming they are not large specimens. You can do 1-2 water changes each day using your tank water to bring up the salinity and keep NH4 levels in the bucket in check. Brackish puffers adapt quickly to changes in salinity - but I would not exceed more than 5-6 ppt each day. Also I would not feed them in the bucket just in case - they will be fine fasting for a couple of days.

Good Luck

[Gavin]

Thanks guys.:)

[karlas]

i agree i would cycle the tank brackish first because the brackish cycle can be almost or just as harsh as a sw cycle. when i first sat up my brackish tank i lost a lot of fish because i did not know about the cycle for it and that was changed from fresh to brackish