# Using calcium reactors for maintaining high ph



## zencakd (Sep 15, 2005)

Dear all,

reef aquarists use calcium reactors to maintain high ph like this one: http://www.peteducation.com/article.cfm?c=16+2148&aid=2979.

Do you think it could be used in tanganyika tank to keep ph above 8? Just curious...

Thank you,

David


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## Toby_H (Apr 15, 2005)

I'll first admit, I've never used one...

Having read the page you linked us to, I don't see any reasons why it wouldn't work in freshwater... although I think it's a very complicated way of solving a very simple problem...

Doing something as simple as using crushed coral as substrate, or even putting crushed coral in an existing filter as media will buffer the PH.

Adding baking soda to water prior to adding it to the tank will raise both KH and PH.

It may be an essential part of some saltwater set ups that have very specific requirements... but freshwater fish are far less dependant on exact numbers...

The general rule with freshwater fish is that it is more important to have a stable PH than an exact PH... So even fish that come from waters with a PH of 8,2 will typically do better at a constant 7.8, than fluctuating from 7.8~8.2...

So if you were to use this unit to give yourself a PH of 8.2... doing typical water chagnes with water that was neutral (7.0)... you should expect to see the overall PH drop when fresh water is added, then creep back up as the reactor does it's thing.

With Saltwater tanks most commercial salt mixtures have additives that buffer the PH of neutral water to 8.2~8.3.


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## cjacob316 (Dec 4, 2008)

they use them for corals, it's pretty essential. if you want to use calcium reactor i assume you have a sump? because that's usually where they are placed, if so, i would suggest filling your sump with aragonite to buffer, it's cheaper than filling your whole tank, and if you use the really coarse grade that just looks like crumbled shells, it would provide a lot of extra surface for bio filtration as well


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## TangSteve (Sep 20, 2009)

A calcium reactor is used on large reef set-ups that have numerous SPS corals using the calcium very quickly.

Calcium is kept close to 400 ppm. In a fresh water set-up with nothing using this calcium the levels would quickly go off the charts and you would start to see impellars locking up due to the calcium.

Smaller reef tanks usually just kalkwasser or a two part dosing solution to add calcium to the tank. Kalkwasser is calcium hydroxide which is a very caustic powder so it is dripped in the tank very slowly typically overnight when pH has dropped some already.


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## Fishbulb2 (Sep 23, 2008)

Wait, wait, wait. A calcium reactor does not increase pH in a reef aquarium. In fact it DECREASES pH. It raises alkalinity and Ca++ in equal parts to replace their depletion during coral growth. Calcium reactors use CO2 to create carbonic acid in a small reactor to drastically decrease the pH in the reactor and dissolve the media (calcium carbonate). Reef tanks are generally held at 8.2 and reactors are between 7.8 and 7.5. Reef tank users generally take the effluent from their reactor and run it over more calcium carbonate to suck up any extra CO2. Or they take the effluent and run it into a protein skimmer to blow off the CO2. Finally, many reefers will use Kalkwasser (CaOH), a strong base, to supplement a calcium reactor and neutralize the pH drop that they cause.

Just use cichlid buffers or very small amounts of NaOH if you are looking for a pH boost.

FB

Correction: Sorry about that, it's been a long time since I've used my calcium reactor. Typically CO2 is used to DROP the pH inside the reactor to 6.5 - 6.7, not 7.8. Do you really want to drip pH 6.5 water into your cichlid tank?


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