Jump to content

CR cannot keep up KH levels in SPS dominated tank


Recommended Posts

  • SRC Member
Tropic MG has more effect than Seachem's? I added 10 full teaspoons to a cup of water and the mg raised by 10-15ppm only!

The fastest & most cost effective way to raise mg (for me) is to use Epson Salt. It can be purchased from NTUC or Guardian. One box of epson salt cost about $3+ & it can increase mg level by about 100ppm for a 4*2*2! :yeah: cannot remember exactly but you can refer to http://ozreef.org/diy/magnesium_additive.html. Hope this help.

Link to comment
Share on other sites

  • SRC Member

Think the best way to do it is to let CR do the dosing by it self, just like Ca. Epsom salt is a very cost effective way but one has to measure the Mg every week or so and then top up with Epsom salt. There will be fluctuations. Like I mentioned, if you mix the ARM with Grotech Mg Pro mixed in correct proportion, then it will be maintain automatically at 1300 mg. Of course to start off with, the Mg has to be 1300mg from the beginning.

Link to comment
Share on other sites

  • 3 weeks later...
  • SRC Member

I think pipping the effluent into the skimmer is not a good idea. First of all, it increase the chance of the CO2 dissolving into the water and hence lowering the PH (more acidic).

Secondly, after mixing with the high ph water, the Calcium in the effluent may start to precipitate and solidify in your skimmer instead of increasing the Calcium in your main tank.

In my opinion, the same thing may happen at the 2nd chamber of the CR too since the CO2 will be consumed by the extra ARM in the 2nd chamber, and when the CO2 is used up, the calcium may precipitate in the 2nd chamber too.

IMHO, the efficiency of the CR is depending on the volume of the CR and how much ARM it can contain. If your CR volume is limited, keep increasing the CO2 bubble will risk releasing more CO2 into the tank.

I think increasing the size of the CR is the only solution.... or scrap away more coraline algae.

Regards,

Patrick

Link to comment
Share on other sites

Many of us think that the low pH of the tank water is caused by excess CO2 in the effluent that has not sufficient time to react and dissolve the media.

Actually the low pH of the tank water is caused by the fact that the CR is adding alkalinity mainly in the form of bicarbonate. The bicarbonate itself will cause the pH of the tank to drop. When the excess CO2 is degassed (eg dripping effluent into protein skimmer etc) then some of the bicarbonate will be converted into carbonate. In case of this, once the water becomes supersaturated with carbonate then the carbonate will be inclined to precipitate onto calcium carbonate surfaces, and some alkalinity will be lost.

Link to comment
Share on other sites

  • SRC Supporter
In my opinion, the same thing may happen at the 2nd chamber of the CR too since the CO2 will be consumed by the extra ARM in the 2nd chamber, and when the CO2 is used up, the calcium may precipitate in the 2nd chamber too.

Do you have any concrete evidence that this happens??

I have done tests on 2nd chambers previously and have found that 1.5 kg of media in 2nd chambers gives a increase in 50ppm and 4 dkH in the effluent after in passes through 2nd chambers....

of course, taking in consideration of design and pH level of the effluent from main CR outlet.....

Link to comment
Share on other sites

  • SRC Member

Anyone figured out why the constant drop in KH???

I dose my KH till 9, then it will drop over the weekend to 7 :pinch:

I dun believe my CR can't handle my small tank, but it's the tuning part <_<

I also ruled out ionic imbalance as I just did a water change. However had not tested my Mg, or Ca :blink:

My SPS have stopped any visible growth and 1 or 2 have signs of receeding base :cry:

Perhaps someone can enlighten me?? :thanks:

Link to comment
Share on other sites

  • SRC Member

CO2 from the atmosphere or from CR will have negative effects on Kalkwasser!

Read the summary of this:

http://reefkeeping.com/issues/2003-05/rhf/feature/index.htm

weisoon,

just came across an article in the recent issue of reefkeeping on "low pH" (http://www.reefkeeping.com/issues/2004-09/rhf/index.htm),..."A final approach, and probably the most successful, is to combine the CaCO3/CO2 reactor with another alkalinity supplementation scheme that raises pH. The most useful method in this application is limewater. In this situation, the limewater is not being used to provide large amounts of calcium or alkalinity, but to soak up some of the excess CO2, and thereby raise the pH. "

maybe not by the input to the KR but by combining thru a "Y" connector on the output of the KR.? .. the low pH would be neutralized by the kalk, as your pH increases so will your dKH?? jus a thot

Link to comment
Share on other sites

  • SRC Member

Have just upgraded my CR to a larger model and have dumped in about 15kg of ARM Media and about 1.5kg of MG Pro.

Now bubbling CO2 at a rate of 1 bubble/2 seconds or so and waiting for the CR to kick in. Have set the target Ph of the reactor to be 6.75 and after tuning, I am very very sure that the Kh and CA values can be maintained without manual dosing.

Link to comment
Share on other sites

  • SRC Member

weisoon,

just came across an article in the recent issue of reefkeeping on "low pH" (http://www.reefkeeping.com/issues/2004-09/rhf/index.htm),..."A final approach, and probably the most successful, is to combine the CaCO3/CO2 reactor with another alkalinity supplementation scheme that raises pH. The most useful method in this application is limewater. In this situation, the limewater is not being used to provide large amounts of calcium or alkalinity, but to soak up some of the excess CO2, and thereby raise the pH. "

maybe not by the input to the KR but by combining thru a "Y" connector on the output of the KR.? .. the low pH would be neutralized by the kalk, as your pH increases so will your dKH?? jus a thot

Evaporation will be top up using the KalkReactor in the night and the during daytime using a dosing pump using distilled water. Whereas the Calcium Reactor will be run 3-4 hours after light on and for about 8 hours duration.

The Deltec units: the Kalkwasser stirrer and the calcium reactor are good products and if you have the chance, do take a look at them and note their working principles. They are value for money.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share




×
×
  • Create New...