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Ronald
04/13/2004, 10:42 AM
Hello Anthony,

I continue to have problems with ca and alk and have used slurry methods to help correct. My ro water has essentially 0 alk and ca, my salt mixes up in normal ranges (1.025/9dKH/350ca, pH 8.3). I have always had low pH chronically even wth excellent skimming,(euroreef skimmer tuned and clean) I think it is the inside air (CO2 is likely high) due to a tight house in a cold climate.

On your advise I began slurry technique Kalk additions which were great as long as I was in town. Kalk/Alk levels were almost good (dKh 9, Ca 300) but if I went out of town, pH fell, Ca dropped, alk dropped etc. :(

This made me set up a kalk reactor with a 3g bottle on a stirring platform with kalk and a dosing pump (cork in place, closed system very little air contact with kalk). I found I needed far more of this solution to maintain ca++ and pH than I needed top off water even with aggressive fanning and evaporation fascilitation.

The next step was to divert some sump water to the kalk reactor directly, and now I use seperate ro top off water and (4 liters/day) and run 15 liters of sump water daily through the bottle with kalk. This maintains pH between 8.2-8.35. I need to add 3 tablespoons of kallk every 2-3 days to the bottle to keep it going and stable. Once every 2-3 weeks I clean out the bottle and start with fresh mixed sea water (aged etc). I also do 2, 5g water changes a week. :) My ca++ and alk still run low (alk about 7-8 dKH and ca++ 250-300) :confused: My stock levels are relatively low, I have a coral garden with 6 fish , 2 euphyllia, some zoos, some porites, very prolific mushrooms, a trachyphilia, a cynarina, and claustrea (excuse spelling errors please) in a 75g tank.

My questions:

How can I stop being a slave to the tank (don't get me wrong, I enjoy it a great deal, but I worry when out of town even for 2-3 days!) I need a continuous ca/alk source that will also stabilize my pH. Balanced additives do work, but I am stuck daily dosing again, I don't trust a dosing pump to accurately deliver them over any length of time. I am worried a Calcium reactor will lower my pH. I have never tested to see how low it will go if left alone, but it easily gets down to 7.9 in 2 days (yes I use a callibrated meter)
Any ideas?

Ron

ps you can see my tank here here (http://homepage.mac.com/ronaldalberico)

Anthony Calfo
04/13/2004, 05:42 PM
Your intuition and decisions overall have been very good and on par in my opinion.

The one thing that jumps out at me is the application of RO water. Is this water being auto topped off raw/direct? If so... yikes!!!! I'm guessing its not the case, perhaps I misinterpreted or read the mail too quick :D But if so, this is a very bad habit and unquestionably some kind of burden on alk and pH. Demineralized water is too soft/acidic and needs to be aerated first (12+ hours) and then buffered/mixed usually (another 12+). Basically, pull pre-treated water from a reserve and not a auto-tap source.

The calcium reactor is a fine idea. If harnessed to a controller to meter the dispsense of CO2 when you are away, you can prevent the aggravation of a fallig pH by letting it turn off the CO2 at a low set point. A low pH is far more stressfull than a flat Ca or ALK level.

And I agree that accumulated CO2 in the house is a likely influence here... but it would be nive to confirm it. Easy enough too. Do take a glass of aquarium water out to the garage (or outside the window, and aerate it for some hours. The pH should not increase with aeration... but if it does. BINGO.

Food for thought :)

Anthony

Ronald
04/13/2004, 10:05 PM
Thanks for the quick reply. The RO water is aerated continuously and mixed with arm& hammer washing soda to get alk into a good range prior to adding to tank. The pH of the RO water is high (about 8.8!) but given the low trending pH in general I thought this was good.

I have always been a little leary of the slurry technique for kalk since reading Julian Sprung's books. Is it really ok to have my sump water circulating through that kalk setup I use? It sure does the trick for pH, I hope there isn't some evil precipitation going on in the bottle though.

Thanks again!

Ron