Setting up and cycling a brackish tank for a GSP

[Crust]

Hi all,

So I've got my tank scaped and ready for a fish. Its just over 3ft long and around 160 litres. I was looking to get a GSP, and I have read the article on fishless cycling on The Puffer Library. Now I am looking to add bacteria to the tank to start the cycling process, but I am unsure what bacteria to buy. I have heard that freshwater beneficial bacteria is different to those found in marine environments; is there a specific start up bacteria for brackish tanks? Furthermore, are these bottled bacteria products any good? I don't have another tank to take media from, and this is my first fish tank.

EDIT: I also wanted to ask about RO & DI water, is it needed for a brackish tank, (for a GSP for example)? I can provide tap water parameters if it would be any help answering this one.

Any help and advice appreciated, many thanks.

[Pufferpunk]

Most BW fish are sold in freshwater. Tetra Safestart is good. You can add it directly to your filter & then add the puffer. Check the parameters fir 2 weeks & if everything remains stable, you can begin adding salt. RODI is not necessary.

[Crust]

Thanks for the quick reply! The LFS has their GSPs in brackish at the moment, so I was thinking of cycling my tank as a brackish tank, would the tetra safestart be suitable for that? I couldn't find any info on their website.