The Puffer Forum

My F8 puffer has been acting strange since my last water change tonight. He's never had a problem with a water change before. With each change I add a little bit of marine salt because he's being transitioned from FW to brackish. This is done gradually, and mixed in with his water and fully dissolved before it's added to his tank. He's in a 15 gallon tank, about a 3/4" F8 puffer. I've tested the water pH is high (my test strips don't give concrete numbers, but I'd say around 8 based on the color the strip shows). Nitrates and Nitrites are 0, salinity is about 1.0001. The aquarium has been set up about a month and a half, and was cycled before he was put in it. I've had him for about a week and a half. He's been really active up until tonight and I'm worried the water change affected him, but I'm not sure how serious that can be, or if it's something he'll have to wait out. He gets fed a couple freeze dried bloodworms in the morning and a small piece of krill at night (I wait until his belly rounds a little and then take the rest out).

Tonight he was just sitting on the bottom of the tank. I know he does this at night, but I tried to get his attention and he still wouldn't move. He went in a stream of air bubbles and didn't seem to have control to swim out of them. He was trying to swim to the other side of the tank, but didn't seem to have the strength for that either. Any thoughts? Do you think this might just be stress? I'm hoping it's something he can just ride out, but I wanted to get other's opinions.

Thanks

When I had f8s I found that right before they died they seems like they couldn't swim. He would swim a little and then float around the tank like he was dead and then I would walk by and he would swim away. I don't know if this is the same problem you are having. When I saw this problem I treated for Ips but I think it was too late. I hope this doesn't happen to you and the others will help you more.

You might want to raise the SG a little faster than that. The system can handle a rise of .002/week. Go ahead & mix up a cup of salt for the tank & add it to your HOB filter.

Thanks. He looks a little better this morning. His stomach has been white, even last night. He seems a little bloated, almost rounded, rather than having his little belly like normal, or a flat stomach. I went ahead and added a little more salt water, just pulling out some of his existing water, dissolving the salt in a container, and then putting it back in. He responded well to that and swam around a little bit. He still seems to be sitting on the bottom mostly, but he's still here, so that's good. I'm planning on skipping feeding today since he doesn't seem to be feeling well. Thanks for everyone's help.

His temp right now is at 78, should/could that be raised to make him less stressed? I know in some other fish they recommend that.

Increased temperature decreases dissolved oxygen in the water, and 78 is about ideal for F8's, I'd leave it be.

Just wanted to thank everyone for their suggestions. Nibbler is doing much better tonight. He appreciated the added salt too.

Thanks!

Glad to hear it

Good to hear things are going better!
I suspect you'd still like to understand what caused the problem so here is one idea you can evaluate to see if it applies. We have very soft slightly acid water and have seen the following in our tanks.

As you bring up the salinity of your tank water by adding marine salt, your water is initially lightly buffered as the marine salts also adjust the pH upward toward pH 8.3 or so. With weakly buffered tank water the pH can quickly drop back down after the buffers added with the salt are overcome by acids produced during nitrification. If you then do a large water change adding new buffer in the marine salt and removing the accumulated acids, the tank pH will make a large sudden upward jump, which is very hard on the fish.

To check for this problem you can check the tank pH before making a water change and compare it to the pH of the replacement water. To prevent the problem you can regulate your tank pH using an appropriate buffer.

Thank you for helping me understand that. I have two other tanks, one that's currently fresh being converted to brackish, for a new GSP, and a fresh for some tiger barbs. The one with the fish who wasn't feeling well was my F8, so I've had just a little bit longer who's on his way to becoming brackish more than any other one in my house.

Brackish aquariums are totally new to me, so I'm really appreciative to get any new information I can. I absolutely love my new brackish aquarium and am looking forward to when they "grow up" and I give them bigger aquariums.

Thanks!