Need help fast! Need to make my freshwater tank brackish!

[SeaShimmer]

Hi, I have a freshwater tank that I have had set up for a couple weeks now. Yesterday I went to the pet store and bought 2 figure eight puffers and a pycosomus (sp?). They're in the tank now. However, I have been reading about puffers online and just realized that they are brackish. The guy at the pet store said nothing about that when I bought them.

What should I do? I just went to the pet store and bought salt so I could try to adjust it to their needs but I'm not really sure how much salt to put in it.

Please help!

 

[Toirtis]

OK, first of all...if the second fish you bought is a plecostomus, it will not tolerate much salt at all, so it needs to be in another tank altogether (possibly a much bigger one, as plecos, depending on species, can reach 24" or more). Secondly, switching a tank from FW to brackish is something that needs to happen quite slowly...like over the course of 6-8 weeks. Thirdly, if you want a proper brackish tank, you should be using a marine salt, not just that stuff that most pet shops sell as 'aqaurium salt'. Lastly, and perhaps most importantly...am I to assume that your tank has been running without fish in it? Did you go through a proper fishless-cycling process, with an ammonia source, frequent water-changes, and water-quality tests (that should have given you 0ppm reading for both ammonia and nitrite before you added fish)?

 

[SeaShimmer]

I believe what you said (plecostomus) is what I have. I had to look up a picture and it looks the same. Mine is pretty tiny. Maybe 2 inches right now. I guess I need to find a new place for it to live.

You said the switch needs to happen slowly, does that just mean putting in tiny amounts of salt until it reaches what it should be? The salt I have is Tropic Marin Sea Salt. Is that alright?

Yes, my tank had been running without fish in it. I thought all you were supposed to do before putting fish into it was let it run with all the proper chemicals put in and make sure the Ph level is ok. So that's what I did before putting them in.

 

[Toirtis]

The Tropic Marin is good, but you have a bit of a problem on your hands...your tank is not cycled (those two weeks were wasted time, I am afraid), and needs to be.

Read here:
http://www.aquariumadvice.com/showquestion.php?faq=2&fldAuto=21
http://www.aquariumadvice.com/showquestion.php?faq=2&fldAuto=15
http://www.aquariumadvice.com/showquestion.php?faq=2&fldAuto=23

 

[SeaShimmer]

I read the articles but I still don't know what I should do. I already have the fish. So is there anything I can do now to make sure everything is ok? And get the switch to brackish started?

 

[Toirtis]

Well, first get a test kit, so you can monitor the ammonia and nitrite levels...and 30% daily water changes should keep the ammonia and nitrite levels below lethal, so long as you are sparing in feeding your fish. After about 15-20 days of that, the tank should be cycled....you will know by using your tests as per the instructions in the cycling articles.

 

[SeaShimmer]

Ok, thank you! One more thing, since I will be making water changes every day, should I start mixing salt into them? If so, how much per gallon?

 

[Toirtis]

I would consider cycling with a salt-level of around 1 tablespoon/gallon...and only raise it after its cycled.

 

[Menagerie]

Hmmmm, I will disagree with Toirtis on this one. After the tank cycles and you start adding salt, the bacteria will be slowly changing to survive in a salty environment. I believe you can start adding salt now, in small increments.

This is the chart we use (full credit goes to my husband for figuring it all out with the instructions on the salt bag and a sensitive hydrometer):
The target is ~15ppt.
The conversion was done looking at full marine ~27 ppt according to the salt bag.

For every part per thousand, you multiple (118.4/27) x the ppt.

1 ppt x (118.4/27) = 4.39ml/gal (It ends up being about a TBLSP/gal)
2.5 ppt x (118.4/27) = 11ml/gal
5 ppt x (118.4/27) = 22ml/gal
10 ppt x (118.4/27) = 44ml/gal
15ppt x (118.4/27) = 66ml/gal

When we converted a FW to BW, it took many weeks. The tank was already established and all the fish were bought as FW, although they are BW. What a difference the salt makes in their behaviors!! My bb gobies are truly loving life in the BW tank.

 

[Toirtis]

Hmmmm, I will disagree with Toirtis on this one. After the tank cycles and you start adding salt, the bacteria will be slowly changing to survive in a salty environment. I believe you can start adding salt now, in small increments.

Not entirely disagreeing with me...but keeping it at a steady, but low salinity during cycling will allow for more quick cycling, reducing the stress on the fish in the tank (and without adding a certain amount of stress as they adapt to climbing salinities, as they have likely been, up to this point, kept in fully fresh water.). Thre impact on the bacteria from changing salinity after cycling, if done slowly, is almost neglible.

 

[MarkLehr]

A note on the salt level. Rule ot thumb, if you add 1/4 cup of salt per 5 gallons of water, you will get up to an acceptable salt level for the tank you are doing. You could raise the salt level in 5 weeks, with a 5 gallon water change each week, replacing what you take out with new brachish mix water at 1/4 cup per 5 gallons.

This is not exact in the salt level, but the very nature of brachish water makes it such that you can have anywhere from 1.005 to 1.015 on your hydrometer reading. FYI, you shoudl purchase a hydrometer to test your salt levels. For a brachish tank, you can spend about $8.00 on a hydrometer which bobs up an down in the water and gives you a wide range of readings. When you see it you will know what I mean. You can use this same hydrometer on a SW tank when you eventually decide to do one.

 

[Toirtis]

A note on the salt level. Rule ot thumb, if you add 1/4 cup of salt per 5 gallons of water, you will get up to an acceptable salt level for the tank you are doing.

Yes, but perhaps a bit much for puffers who have spent the past several weeks in nothing but purely freshwater.

 

[MarkLehr]

re: raising salt level

I also wrote:

You could raise the salt level in 5 weeks, with a 5 gallon water change each week, replacing what you take out with new brachish mix water at 1/4 cup per 5 gallons.

Which would gradually bring your level up without stressing out your fish.

Good luck!

 

[Menagerie]

Sounds good. Take both Toirtis' and MarkLehr's advice. Add salt slowly and your puffers will love you for it!!