The Puffer Forum

i have a new 30 gallon tank going i read in one article about using sand on the bottom question i already bought 2 bags of natural stones for the bottom is it necessary to change this out ?

What kind of fish will you have? I guess it will be a brackish tank, right? If it will be a low end brackish water, then you won't have problem using the bags of natural stones you already bought.

If your personal choice is sandy bottom, then could you go back to the LFS and change the bags of stones to sand?

thank-you for your reply fernando i will keep the stones, also i saw a most beautiful white (silver ) mollie can this fish live in the puffer tank or no way Jose??? thanks suzie-q

mollies as far as i know can do well in brackish waters - but it will depend on the puffer i think, if it will survive possible attacks from the puffer

It'll depend on each puffer... some puffers will get along with mollies, some puffers will kill mollies and another puffers will be bullied by some mollies. So, if you wanna run the risk, keep an eye on them.

Actually, brackish tanks do best with aragonite substrates. Next best is crushed coral substrates. Puffers are high bioload fish ,the extra alkalinity reserve Of carbonates/bicarbonates from those substrates assists in keeping the water stable. Natural stones and silica sand do not help there at all.

Richard, isn't the carbonates and bicarbonates provided by marine salt enough to keep a high pH when you keep SG at 1.003-1.005 for F8s?

When SG in my F8s' tank is at 1.005 my KH = 4º and the pH is around 7.8, I'm saying that because my tap water is really soft with high pH ( KH/GH < 1º, pH = 8.0).

The molly question, that depends. Mollies can get quite large (females especially) and a 30 gallon tank isn't really that big. So depending on what the puffer will be, maybe. A figure 8 and a molly in a 30 gallon, I'd say yes. A GSP will need all 30 gallons for itself, so no additional tankmates. But yes, mollies can handle the salt, and sometimes they actually bully puffers because they are so outgoing and active... they get to food first and tend to make the puffers nervous. I personally think it can be done, but only in larger tanks where everyone has plenty of room. In a 30 gallon, I probably would not try.

By_a_coo wrote:Richard, isn't the carbonates and bicarbonates provided by marine salt enough to keep a high pH when you keep SG at 1.003-1.005 for F8s?

Not at such a low SG. For marine tanks, yes. It's Robert, BTW.

Pufferpunk wrote:It's Robert, BTW.

I always get confused with his first name.

RTR works.

Yup, it is Robert, and PP is also correct on the alkalinity/GH. 1.003 has no more alkalinity than some feeshwater tap sources, and F-8s are high bioload fish, so use up alkalinity/bicarbonates beyond what you might expect from non-puffer fish. Stability seems important to them.

That does not seem rational for a BW fish, but it seems to work that way for me with captive F-8s.

Thank you both in clarify that!

Could it be an idea having aragonite sand or crushed coral in a bag inside the filter if someone wants to use another type of sand or gravel to compose the aquascape?

Many folks do that. You'll just have to keep an eye on whether it keeps the pH stable or not that way.

I had to use crushed coral rubble - not a standard substrate, it is very coarse material - in a canister for my office FW tank. The KH was very low from the tap. I used two bags, alternating them every 2-3 weeks with rinsing and drying in between. I chose the less soluble material because it did have a good bit of surface exposed to water flow, so I did get effective buffering (by KH testing). I got better results than from aragonite sand in this use due to better flow-through of the coarser rubble - sand can be hard to penetrate by flow. The rinsing/drying was to kill off the biofilms that form on any underwater surface - sometimes they help, sometimes they hurt - so i did not want to leave it to chance. When you are working with much less surface area than a whole tank substrate, you do need to maximize water exposure.

HTH