Extremely Soft Water

[aklaum]

I probably should have done this much sooner, but I just tested some tap water that was aged for 24 hours. Results...

pH: 6.6
KH: 0

So, not good. This explains why I had a stall in my fishless cycle and why a 90% water change did nothing to raise the pH or KH. I fixed that by adding baking soda, but I assume you can't just dump in a bunch of baking soda once there are fish in there.

So, as this is going to be my source water for this tank and all future tanks I need a long term strategy for keeping pH and KH levels at a safe level.

I am theorizing that a good time to do whatever adjustments are necessary would be during weekly water changes, but what to adjust with?

Is there something I could scientifically measure and add specific amounts of to each water change?

I noticed crushed coral being mentioned on some other threads. I do have some aragonite handy. How can it be used? As this is going to be a long term problem I need something that is going to be as controlled and repeatable as possible.


MORE IMPORTANTLY:

My fishless cycle is complete and I was planning on getting fish tomorrow. Before doing this I was going to do the recommended 90% water change to eliminate the nitrates.

I'm afraid I am going to dramatically lower the pH and KH of the tank with the water change. What should I do tomorrow to make sure I have a reasonable pH, KH for our new charges?

[OrionGirl]

You will want to make modifications to the water you use to do the change, so you don't remove all the buffers added to the existing water. It sounds like you are aging your water, so you can make the additions to it there, to bring it up to the same/close parameters as the tank water. Adding a small baggie of aragonite to the filter will help maintain the buffers in the tank without requiring daily additions. It's all about stability--getting the water for changes close, and then helping it stay at that KH/pH in between.

[RTR]

Agree w/OG. The aragonite is IMHO & IME better than crushed coral, as it dissolves more easily, which is a plus. There a feedback to these materials, as the lower the pH and hardness, the better/faster they dissolve. This helps the stabiliy long term as well. Most folks have to juggle the amount a bit to get the end point where they want it, but that is just adding or removing some aragonite by smallish spoonfuls, not large quanties.

The simplest correction is to get the tap close before use with bicarb addition, and a couple of test buckets will give you an idea of how much is needed before adding to the tank and after that it just add a certain quantity before you use the water. Bicarb dissolves very fast, this is no problem for you. Then the aragonite can maintain the tank stable.

[wesleydnunder]

Are you planning to keep discus? I would have killed to have your water back when I was raising discus. I was using RO water from the dialysis clinic I where I worked to make up my tank water.

Mark

[aklaum]

wesleydnunder,

I hadn't thought about discus. However, yesterday I acquired a used 30 gallon tank, heater, filter and powerhead for $25. Is it possible to comfortably keep any discus in a 30 gallon?

What about Cichlids? Anything possible with a 30 gallon?

[aklaum]

Thank you both. I made a little baggie out of some nylon screen I had and put a handful of aragonite in it. I put this in the filter on top of the top layer (I have a three layer AquaClear 50) so that the water flows through it.

So in review:

1. I can use baking soda in makeup water if the pH needs adjusting (in the up direction that is).

2. The aragonite in my filter will act as a buffer and keep the pH stable as well as maintain KH levels.

Correct?

[wesleydnunder]

You might be able to house two in a 30, though I would go larger if possible. I kept four in a heavily-planted 55 and always thought they would be happier in a 75 or larger.

Mark

[RTR]

That sounds good to me, alkaum. You will likely have to monitor the tank a bit the first few weeks before it becomes routine, after that just periodically to make sure it is behaving as you want it to do.