The Puffer Forum

So...I've had a tank for about 5yrs now, I have always wanted a puffer so I recently change my fresh water tank into a brackish water tank. I changed the substrate from gravel to sand, got a canister eheim filter, a new heater, and used my old power head. I set up my tank and let it settle for a week and a bit, I ran my filter, etc...I put in two nylons full of my old gravel to get the bio filter going.

My lps finally got some small Figure 8's in and I got one, I asked what the gravity of the water was but the lady wasn't sure. She said that it was constantly changing with water changes, etc...so its more like their natural habitat. So I had "Spexx" in my tank for just under a week before I added any instant ocean. I put in about 5 tbl spoons, and measured it with my hydrometer, but it wasn't registering...then after a few days I realized that it didn't read low enough for a brackish set up. Then I got a better hyrdometer and the gravity was at 1.006, the next week I added more salt and moved it up to 1.010. I left at that for another week, then I did a water change and topped up the salt to 1.012.

Spexx had been doing fine in the above conditions, I would feed him frozen brine shrimp, a few small snails, or squid every day until his belly had a slight bulge. This past weekend I went away and before I did he was fine, I left a little chunk of brine for my mom to feed him and she did. He didn't get fed the saturday and I resumed his feedings on the sunday. I read somewhere on the forum that it was good to miss one feeding a week to simulate how things would be in the wild.

This brings me to yesterday/last night when things seemed to go down hill. I usually sit on a stool infront of my tank and watch him for a bit, he come out and know its about time to fill his bella. Yesterday I couldn't find him, then I see him hiding at the back of the tank near some plants. He came out and I fed him some squid, he didn't seem to like it much and spit most of it out as soon has he sucked in. So I figured I'd give him a small snail since it had been awhile since the last one. Spexx did he regular bit and went at it, then he got a grain of sand stuck in his mouth and couldn't seem to get rid of it. I turned my back and it was gone, I am not sure if he was able to spit it out or swallowed it. He went at the snail a little more then lost interest in it and let it live...I thought "wow its this snails lucky day". Then Spexx resumed his little hiding bit and seemed a bit off, as the night progressed he lost his lustre and energy and kind of drifted with the water flow. I check the ph and gravity and they were both fine, so then I thought about the nitrate, etc...I didn't have testing kits for anything besides ph though.

Later while in bed I couldn't sleep, I came down to check on Spexx and the poor bugger was sucked to the tube I have attached to my powerhead. So I immediately unplugged it to free him, he kind of swam/floated around a bit without putting an energy into it. He seemed to have laboured breathing at this point too, before going back to bed I turned of the air flow, kept the powerhead off, and reduce the flow from my filter to make it easier for him.

This morning my poor Spexx was laying peacefully in a plant near the front of my tank.

I was kind of ticked and couldn't think of what may have caused him to deteriorate so quickly...was it the grain of sand?? was it the gas levels??

So I picked up nitrate and amonia testers...this is what all of the levels were at...
7.7-7.9 ph
1.006 gravity
0 amonia
20-50 nitrate (fresh water reading)
50-100 nitrate (salt water reading)


So if you took the time to read this novel, could you please please give me your take on what may have happened or what I need to adjust, etc... I would really appreciate any feedback or advice because I want to get another F8 but don't want the same fate for him!

How big was the tank?

Raising the salinity that quickly likely killed any bacterial culture you had going.

The hydrometer could also be very inaccurate and your salt level could be much higher than what you thought it was.

Those nitrates are very high. If the tank was cycling with the fish in it, he likely died from that.

sorry for your loss.

sorry...my tank is a 20gl tank, geez, I hope I didn't kill any bacteria I had. Any suggestions to replenishing them and how to keep the nitrate at a good level??

F8 puffers only require a SG of 1.005. I'd recycle the tank by the fishless method, at whatever SG the fish are being kept at from the store & then slowly raise the SG .001-002/week.

Check our Library for more info.

The only way to keep nitrates down is water changes. We recommended 50% changes each week, more if the tank is cycling.