Soft Water + Low Ph = Stalled Cycle

[nckate]

All right, got back from the lfs and the guy there was no help whatsoever. You would be proud to know that I refused to buy any of the pH up or steady-pH stuff. Phosphates bad.

Tonight's test results (tank):
pH between 5 and 6 (closer to 6) on the API Pond wide-range kit, still below 6.0 on the standard API kit
ammonia 1.5
nitrite 0
nitrate 0
GH 3 deg
KH 1 deg

... so the next question is how to raise my KH so that my pH comes up and holds steady? The only aragonite/coral sand I found came in 20 pound bags. Would adding baking soda with every water change help until I find a better way? If so, how much? I can hold off on the water change until tomorrow morning if necessary.

Fish are doing fine, btw. I dropped a bit of flake in for them and now they're much more active (they had been very quiet and staying-in-one-place.) That should hold them for the next day or so.

 

[Tessla]

pH up/down and steady stuff are a waste of money, phosphates bad indeed. I'd go for a KH of about 4, but I'd also increase that slowly so that you don't shock your fish any more than necessary. Excellent article on GH and KH here. Here's a bit from the middle:

One teaspoon (about 6 grams) of sodium bicarbonate (NaHCO3) per 50 liters of water will increase KH by 4 degrees and will not increase general hardness. Two teaspoons (about 4 grams) of calcium carbonate (CaCO3) per 50 liters of water will increase both KH and GH by 4 degrees. Different proportions of each can be used to get the correct KH/GH balance dictated by the fish and plants in the tank. Since it is difficult to accurately measure small quantities of dry chemicals at home, a test kit should be used to verify the actual KH and GH that is achieved.

Keep up the water changes to keep the ammonia down anyways as that will cause your pH to fluctuate if you allow it to increase.

 

[nckate]

I'd go for a KH of about 4, but I'd also increase that slowly so that you don't shock your fish any more than necessary

I really should have read that more carefully before I went and dumped 2 tsp of baking soda in with today's 50% water change. One more panicked ~30% water change later ...

pH 7.4
kH 4 dH
NH3 0.5 ppm

I'll keep checking on them and give y'all an update tomorrow morning. So far, the gouramis aren't too stressed to chase each other around the tank, and the plec's not too stressed to guard his bit of wafer jealously. (I'll remove whatever he hasn't eaten in an hour, but he hadn't had anything to eat in a couple of days.)

And yes, I know that was a big screw-up. Trust me.

 

[rdd1952]

I would seriously look into hanging a small pack of crushed coral in the tank. It will raise your pH naturally or in your case, give some buffering capacity to keep it from dropping so low. Here is a thread from someone who is using it to raise well water with a pH of 5.0 to 7.8 in his tank. You would only need a small amount. Ask at the fish store if they havve any they can gie you or if they know of someone that would give you some. If you can't find it locally, I'd be glad to send you some.

 

[Maxta]

Would it be worth me buying some crushed coral for my tank to raise its pH whilst cycling? Just my pH has plummeted again and ammonia levels have stayed constant the past two days. However its hard to determine whether this is because iv changed half of my media, or because of the pH. Hmm.

 

[Tessla]

I wouldn't use crushed coral or baking soda without first getting a GH and KH reading on your tank, you should be able to take a water sample in to your LFS.