New to Brackish Tanks

[Grey]

I love GSP's so much I want to set up a 55 gallon for a few of em'.
I've done salt and fresh, but I've never tried brackish out.
First and foremost do you need RO water for brackish or do you just mix your tap water?
I want a white sand substrate, can I use Live Rock (the stuff for salt water aquariums*just to clear that up right now*) or will the lower salinity kill off all the calcerous algae or will calcerous algae continue to grow?
I'm pretty sure the addition of live rock will also aid me in a fishless cycle.
I'm also thinking about getting a mudskipper aswell. Seen this on youtube and I would really like to replicate this in my 75 gallon display.
http://www.youtube.com/watch?v=b0XuQjuY5l4
Is this just a pipe dream or can a puffer and mudskipper be placed together in say a 75 gallon permanently???????
I'm assuming since brackish water is salty then it has a alkaline ph.
Thanks in advance,
Joe

[mikeosoft]

The mudskipper may work, but IMO the chances of your puffer taking a bite out of the mudskipper is high. FYI the puffer shown in the video is a Figure 8 puffer and IME they tend to be less aggressive than GSP's.

GSP's will require high end brackish to full salt water (1.018-1.025) when they are adults. Figure 8's are best kept at low end brackish (1.005-1.008).

The recommended minimum tank size for a single GSP is 30 gallons, which IMO is even a little small for a full grown GSP. They can be quite aggressive when they're adults, so I would only put a single GSP in a 55 gallon tank. Not to mention the bio-load from a puffer is huge.

IMO you don't need to use RO water unless you are going to grow corals. The main reasons for using RO water are to control algae growth and to prevent unknown contaminants from killing your corals (most fish are much less sensitive, as long are you're using a good dechlorinator and your water is free of ammonia).

The calcareous algae (usually called coralline algae) probably won’t survive below a salinity of 1.018 or 1.019. You could add the white aragonite sand now, and then wait until the puffer is adjusted to full marine before you add the live-rock. If you can find a puffer that's already living in full salt water, then go straight for live rock.

IMO you don't need to use RO water unless you are going to grow corals. The main reasons for using RO water are to control algae growth and to prevent unknown contaminents from killing your corals (most fish are much less sensitive, as long are you're using a good dechlorinator and your water is free of ammonia).

The calcerous algae (usually called coraline algae) probably wont survive below a salinity of 1.018 or 1.019. You could add the white aragonite sand now, then wait until the puffer is adjusted to full marine before you add the live-rock. If you can find a puffer that's already living in full salt water, then go straight for live rock.

[Grey]

Thanks so much for the reply.
Your answer has me somewhat dumbfounded I must admit.
This next question should probably be moved to an entire different section which I'm probably going to do to.
When I first started doing marine tanks all I heard and read "USE RO WATER ONLY", I would say "even if I'm just going to do a FOWLR setup" their reply "USE RO WATER ONLY!!"
I knew for a reef setup my tap water would contain bad things like copper, but I never really knew why it would hurt a fish.

Have you ever setup a FOWLR or FO tank with tap water.
If so I'm totally going to take that 75 gallon display tank in the living room and switch it over to Saltwater, and then after its nice and broke in.
I'm gonna put (this is my opinion) the cadillac of puffers in there. 1 dogface.

[SpockthePuffer]

I have a fish only tank with live rock using tap water and I've been having some issues with algae. I haven't figured it out yet and I was getting help on here but its probably because of something in my tap water. Everyone on here said that I need to use RO water.

For my brackish tank I just use tap water and Milton (GSP) has been fine and I haven't had the algae problem like I've had with the sw tank.

[Pufferpunk]

Untill I started keeping corals, I only used tap water. I had a GSP tank w/o live rock, sump or fuge. Did 50% weekly WC on that tank (10 cups of salt/week).

[mikeosoft]

I've done FOWLR with tap water and reefs with RO water. I honestly think my tap water is good enough to use in the reef but I don't risk it. I even use tap water for my baby seahorse tanks and everything has been fine.