The Puffer Forum

My new Fahaka "Buzz" is coming in the morning (currently 2:50am here), and although his 150 gallon tank is fully cycled, I tested for ph today and it was 8.4. Our tapwater is 7.4-7.6, so I'm trying to figure out what's going on. It has 60 pounds of white and black sand from Petco in it, a ceramic log hideout, and that's it. Even after adding Seachem neutral ph it's still 8.2. I haven't used Petco sand before, and it says on the package that it will not affecte water chemistry. Any ideas for what's going on?

Did you test the alkalinity (KH) of the tank and tap water? Without those measures there is no way to respond to your question.

Adding commercial buffers and so-called rtegulators to your tank is one of the most effective ways I know of totally hosing the water chemistry. It is also called shooting yourself in the foot. Don't.

Did you do a baseline nitrate test on the tank and tap?

Has the tank been cycled?

Fahakas are native to large rivers and well adapted to wide variety of pH readings in the course of a year. The pH of the tank is trivial to them.

How exactly has his tank been cycled? Is that aragonite sand?

I haven't tested alkalinity before, so bought a test this morning. Tap water KH is 9 (well water), and tank Kh is 3.3. I'm very familiar with ph, ammonia, nitrite, and nitrate parameters, but have not worked with KH before this.

Tap water nitrate is less than 5ppm

The tank has been cycled for the past 2 months using large bala sharks with weekly 25% water changes since their nitrates never got above 5 ppm. Ammonia and Nitrites read out at 0.

I know what kind of sands I have in my other setups (Tahitian Moon, Aragonite, etc.), but am unsure of what this Petco sand is. The package doesn't say. It says http://www.petco.com/product/115883/PET ... -Sand.aspx. I'm wishing I had looked more carefully before buying it, but the sand has been in there for several weeks, but I admittedly wasn't testing my water as often since it was stable. That's why I'm thinking it might be the sand.

Knowing that Fahaka's don't mind ph changes much helps alot. I will probably throw out the Seachem Neutral Regulator and get a different water conditioner that doesn't claim to affect ph.

that looks like what i got, its not aragonite.

Have you had any problems with it affecting your water chemistry?

just set the tank up(gfs tank) dont even have a filter yet so i have tested anything

If your source water KH is 9, and your tank water KH is 3.3, the tank is approaching a crash (Fahakas are very high bioload fish). You have used up 2/3 of your alkalinity (it is used up in nitrification and is replenished by water changes). You need to go to 50% weekly partials immediately. and it might be wise to do a couple of partials at the 50% level just a couple of days apart to get the tank back up to safer operating levels. In the best of all possible worlds, the KH in the tank would match the source water, but on-going nitrification guarantees that they can never really match - the tank is always a bit lower alkalinity/KH, but for safety it should only be a bit lower when your source water is only moderately alkaline.

Some hobbyist try to replenish bicarbonate, but that actually is high-risk if not very carefully handled. Water changes are mush safer and do more to help maintain a healthy tank.

HTH

I'm going to do a lot more research on KH. To be honest, this tank should be the absolute cleanest and healthiest of my tanks when looking at ammonia, nitrites, and nitrates. It appears that something along the way has messed that up. (I'm still wondering at the sand?) I might move my Fahaka to a temporary 75 gallon and just start over with this tank. (sigh, more cycling). Thank you for your input.

For every milliequavelent of ammonia oxidized to nitrate, two milliequivalents of bicarbonate are destroyed. In other words, if your water partials are perfect for nitrate, you are doing exactly half enough for the KH.

A lot of folks get caught on that barb.