Hello everyone!!! I am doing lots of research on how to change my freshwater 15 gallon tank over to a brackish tank and I am getting lots of good information. One question I am not sure of is if I am going to need a powerhead for circulation or if a bubble bar and my filter will be enough. Right now I have an aquaclear 30 power filter (150gph) and a 6 inch bubble bar. Any advice would be greatly appreciated. Also, any advice on brackish fish for a 15 gallon would be great too. Would it be appropriate to keep my freshwater mollies? Thanks everyone!

You do not NEED a powerhead.. that is up to you, you could, but you don't need it depending on the size of your tank(s), and what kind of fitration you are using. Not many people do brackish so this should be an interesting learning experience for you! (I know it was for me! LOL).. Start with the right kind of salt.. add a little bit every couple days.. take your time, let the children acclimate, and make sure that you are keeping fish that CAN. But in this case, slow is fast. Doing things with patience will pay off! Take your time, make sure you have invertabrates that can tolerate brackish water. Most require it to reproduce, but not all.. some cannot tolerate it, so check that and make sure. This includes shrimp and snails and such like. Make sure you have a way to measure the salt in your water. (salinity). Make sure you are working toward the right mark, and keep testing your water!! LOL.. that's a lot to "make sure" of! (grin).. Good luck!

Yes! There are a lot of things to make sure of. I'm trying to do a lot of research before I even start. Thanks so much for the advice!

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15 Gallon FW Planted

2 Platys
4 Red Minor Tetras
4 Green Cory Cats
2 Ghost Shrimp
and 3 Molly Fry

Mollies are great starter fishes for a brackish water tank. Place them in a pure freshwater tank and slowly adjust them to brackish water through water changes. I would suggest you make a 10% water change every few days with pure saltwater until you get to your desired salinity. Remember that BIg Box stores will usually keep their mollies in pure water so always transition them slowly to saltwater.

bumblebee gobies are cute and can be kept in a fairly small BW tank.