Help Needed: Changing Substrate in Established Tank

[PuffinTough]

Hey Puff Family,

I have a well established 75G freshwater tank with regular aquarium gravel substrate. I recently received two 1" Ceylon Puffers that are happy and eating. I will begin the change over to brackish and full marine as they grow and over time. As a first step, yesterday I bought 60lbs of argonite sand. My question is:

Can I remove the old substrate and add the sand to the tank now?

Or should I add the sand in increments because adding it all at once it will throw of the pH?

I just don't want to cause a spike of some sort and stress the fish.

Please help and thank you!

[hadla]

Was wondering the same thing, my Ceylon started in fresh, now in brackish, going to full salt. There's flourite and gravel in there and I don't know when to take it out to put in crushed coral

[Pufferpunk]

Forget CC, it traps too much detritus in there. Better to use aragonite sand for BW or play sand for SW. If the tank is well-established, I wouldn't worry much about changing out the whole thing.

[hadla]

Oh. I have two buckets full of it... wish I could trade it for sand

[Pufferpunk]

Do this right or you're going to have problems. Look up issues with CC.