Figure 8 Questions

[Rudy]

Very close to getting my F8 as my new 20 gal is fully cycled but just have a question about the water. I went to my LFS yesterday to see if they had some F8's in stock, they had three juveniles, I asked them what the SG was of their brackish water and they told me that they keep them in fresh and then slowly transition them to brackish as they age, they told me not to start them in brackish because as juveniles they are naturally in fresh and move to brackish slowly as adults. So I scratched my head and went to another nearby LFS that has F8's and was told they keep theirs in brackish water all the time, from young to adult. OK so now as a "noob' to this I am totally confused, any advice would be most welcome.
Thanks!!

[Pufferpunk]

In the wild, F8s are FW fish but live in VERY hard water. To mimic the hardness, you can either keep them in low-end BW or add every single trace mineral found in their natural waters. I pick the 1st method.

[bertie 83]

It's certainly more cost effective to take the first option lol

[Rudy]

Thanks for the info! Do you see a problem with purchasing one from a FW environment (LFS) and then adding it to an already established low end brackish environment say around 1.002?

[Arny]

Thanks for the info! Do you see a problem with purchasing one from a FW environment (LFS) and then adding it to an already established low end brackish environment say around 1.002?

When you bring him home put him in a bucket with the water he came in the bag with. Get some air tube and tie a loose knot in it. Then using the tube syphon water from your bw tank into the bucket with the f8 in it. You can adjust the speed of the water going into the bucket by loosening or tightening the knot on the air tube. This will acclimatise the f8 to the tanks brackish water. Do it slowley though to make sure it doesnt shock him.

[sgtmyers88]

If it helps I did that with my GSP's and they did fine.

[Rudy]

Thanks for the reply's! I just received some advice from another F8 owner. He bought his from a LFS that had it in fresh water, he waited a couple weeks for the puffer to acclimate to the new tank and then did a five gallon water change and replaced it with 5 gals. of 1.002 BW. He did this gradual change over a five week period so as not to stress the puffer or kill his bio system. Sounded like a good plan, any opinions on this approach?

[G S P Freak]

He made it far more complicated than it needed to be! If you current tank is cycled already you can just go ahead and raise the SG to 1.002 and acclimate the puffer.
after that just do a 50% WC with a certain SG until you reach the desired SG.
OR you can just jump the SG to 1.004 and add tetra-safestart bacteria (whole bottle) and throw the puffer right in (after acclimation ofc), this is what I did.

[Pufferpunk]

I agree--BW fish often go thru quick SG changes in their day. Sometimes the ocean will flow into the BW streams, making it higher & a good rainfall will have water running down the mountains, lowering the SG of the streams.

[RTR]

Not part of the initial tank adaptation, but pushing SG changes too quickly in the overlap range from FW cycle bacteria and SW bacterial form can easily crash the tank. If you are conservative, the changes from SG ~1.007 to ~1.013 should not exceed 0.002 per week or longer if ammonia or nitrite tests show positive. Killing off the FW bacteria before the SW forms are established is shooting yourself in the foot.

Fish can be drip-adapted pretty quickly. Cycle bacteria cannot. You have to give the colonies time to grow to sufficient size to handle the bioload. For bacteria, theses are very slow-growing.

[Rudy]

OK, sorry for the delay in getting back on topic as I was called away on business. My 20 gal FW tank is completely cycled and is now officially home to one solitary F8! He was raised in FW at the LFS and is in great shape, nice white rounded belly, eating great (frozen bloodworms and small snails) very active and curious, not surfing the glass at all. I would like to start slowly transitioning him to low end BW now and am very nervous about stressing him and crashing my bio, my thought from what I have been researching is to do a normal weekly water change of three gallons and replacing the three gallons with BW water using marine salt with a SPG of 1.002 which is roughly 1 tablespoon of salt/gallon. My goal would ultimately be a SPG of 1.003 to 1.004 in the tank. Does this sound about right? Any input would be greatly appreciated!

[Rudy]

Oh forgot one question, when you add water to a BW tank due to evaporation, does it have to be BW with the same SPG or do you add FW so you don't concentrate the existing salinity?
Thanks again!!

[Pufferpunk]

You add FW to a BW tank to top off due to evap. Otherwise, your SG will raise. The only thing that evaps is water, not salt.

[RTR]

I'm a bit confused - Are you saying you only change 3 gallons per week in a 20 (nominal) gallon tank? For most of us, that is not nearly enough. What is the nitrate level in your tank water and in your tap water? Also, do you have liquid-based test kits for ammonia, nitrite, and nitrate and for alkalinity/carbonate hardness? These fish do need some alkalinity/carbonate hardness (a.k.a. KH) as well as low nitrate levels.

Tanks do not of course hold their nominal volumes of water, but somewhere in the neighborhood of ~70% of the nominal volume. Our standard water change for a 20 would be ~7 gallons per week minimum. As puffers are such messy fish, we do tend to increase the water changes levels a bit beyond that to allow enough vacuuming to get as much debris and waste out as possible.

[Rudy]

I normally do anywhere from three to five gallon water changes every week along with thorough vacuuming. I do use a an API test kit and all levels are 0, as for my pH it is always steady at 7.8. I double stack my Marineland Penguin 150 with media along with a Purigen media pad. I changed out four gallons last night and replaced one of the four with SW @ 1.004 SG. All went very well, Puffer was active and showed no signs of stress. I am planning on doing this BW transition very slowly over the course of a few weeks the same way. Ultimate goal is to be between 1.002 and 1.003 when all said and done.