Q's about methods for increasing kH with aragonite/coral

[simonero]

I have a tank that is CONSTANTLY/always dealing with low kH issues. It's the water in my area. I'm worried about pH shock for a new, juvenile tankmate next time I have to do a substantial water change. Trying to decide if I should multi-task the function of a new decoration I must acquire for structure, or deal with kH separately.

[Tank is 55gal freshwater, lightly planted w/1 anubias, low stock/bioload. I have live aragonite in 2 running "backup" filters already.]

Answers to any of the following would help:

(1) Will more crushed coral/aragonite be as beneficial as a ~2.5-5in (largest dimension) piece of either, out of the filter? Will they lose their buffering properties more or less quickly as they sit in the water over time?
(2) Would you recommend aragonite over coral (or vice versa)? Or are they about the same?
(3) Is it worth dumping some crushed live aragonite in as sand? I have SO much, but don't want to add more sand unless the pros (buffering for a good while) out-weight the cons (more space for hidden nitrite pockets/waste).
(4) Any other cost-effective but helpful, "natural" ideas? Or other, cheaper rocks/crystals to consider? (already maxed out aeration)

Feel free to point me to another thread/page if there is one with answers, but direct answers are appreciated too! And the more answers/thoughts the merrier! Thank you so much!!

 

[StevenF]

For starters what is your PH, KH, and general hardness right now (Tap and tank)?

 

[StevenF]

While I am waiting for your reply here is some very basic information on calcium carbonate (the primary ingredient in Aragonite).

Will more crushed coral/aragonite be as beneficial as a ~2.5-5in (largest dimension) piece of either, out of the filter?

It doesn't mater if it is in or out of the filter. If you put it in the filter use the larger pieces. fine crushed coral or aragonite may pack down and restrict filter flow. You could scatter the smaller pieces throughout the aquarium but if you do and fore whatever reason decide you don't want it in there anymore, you probably would never be able to find all the pieces. I think inside the filter is a better place because there is a lot of water flow there.

Will they lose their buffering properties more or less quickly as they sit in the water over time?

Yes and NO. The buffering occurs when it deserves in water. When it all Dissolves away and is removed in a water change you will have no more buffering. A solid piece has no buffering capability. Only when it dissolves will it provide buffering.

Would you recommend aragonite over coral (or vice versa)? Or are they about the same?

Aragonite, coral and sea shells are all Calcium carbonate (with small amount of impurities mixed in. They all do the same thing. Cost and size is the big difference. Other than calcium carbonate, magnesium carbonate (dolomite. will also buffer PH. Calcium carbonate and magnesium carbonate are manufactured today buy the ton and high purity powders (99% pure) are readily available.Sodium Bicarbonate (baking soda) will also buffer PH but you have to be careful with it because it easily dissolved and water and if you put too much in, it will rase the PH and KH up too much.

(already maxed out aeration)

Aeration has no effect on KH. It does however stabilize the amount of CO2 in your tank which does affect PH.