Fixing my brackish aquarium and tips

[pandalove182]

So right now I have a sickly Green spotted pufferfish and I dont know if hes going to make if he doesnt I would like the set my tank so that it would be a better environment for a GSP. I have a 30 gallon tank with about a dozen plants and a small structure for a the fish to plan in. I have a gravel bottom with an under gravel filter. I had my water tested and everything is fine except for the pH its about 8.0 and I have been doing water changes daily with bottled water. The salinity is about 1.007. Before I had my GSP I had 2 snook chiclids which died when my bros gf tried turing off the tank light and twisted my heater to max and boiled my fish. (shes not allowed in my room anymore). SInce they died my tank has been without fish for 4 months when I finally turned it brackish 2 weeks prior to buying my GSP. I was told that maybe the bacteria died in my tank if so how could I reboot my tank and with what fish? Also, should I switch the rocks for sand? How long would you recommend I recycle my tank before introducing new puffers? If anyone would like to give me any pointers for my future puffers that would be greatly appreciated.

Thanks

[Pufferpunk]

pH of 8 is what you are looking for in a BW tank.

[pandalove182]

So my pH is even and my puffer isnt hiding in the corner hes kind of at the front now moving a little bit more buy has a dark color. I also noticed that the ghost shrimp in my tank are swimming around in the water. Their not just crawling at the bottom their swimming at the top and at mid-tank is their something going on?

[Nick]

Did you ever clean out that under gravel filter? Waste builds up forever in them.

[pandalove182]

Ive never taken it out but I mean this tank is only about a year old and I have a 55 and a 45 that have been set up for 3 yrs and 5 yrs and ive never taken out the under gravel filter and everything in those tanks are perfect

[Pufferpunk]

I hate those things! Like sweeping dirt under the rug.

[pandalove182]

Do you guys think that it would be a good idea to cycle my fish tank with another fish? I have a firemouth chiclid in another tank thats been beaten up pretty bad I might be able to use him or maybe goldfish. Im not sure and how long do you think I should cycle with this new fish before reintroducing another pufferfish?

[Nick]

If you have another tank with a power filter, you can cycle the new one with a well-used filter pad from the old one in basically zero time.