Ok, heliguy lets get back to helping you.
Take a step back, take a deep breath, and relax. A pH of 8.0 isn't bad. You seem very focused on numbers, but we haven't heard any indication of why you want to raise the pH other than just for the purpose of chasing numbers. Ask yourself why your trying to raise the pH in the first place??
It sounds like your ca is pretty low and I don't believe you've even tested your mag. You need to remember that reef chemistry is a very intricate balance of many elements. Ca, mag, alk, and pH are all very closely related and each one has an effect on the other. There is a lot to learn about reef chemistry and there is a steep learning curve to go with it. Acting and intervening, without a full understanding of what the implications are of what your doing, will likely result in undesireable results and further frustration.
My last few suggestions.
1) Stop being so fixated on your pH. The first step in getting your pH in line needs to start with getting your ca, mag, and alk within acceptable parameters. Focus on getting the basic elements in line and that will open the door to allow the pH to be further elevated.
2) Do some thorough research on reef chemistry and the various means of maintaining those critical elements. There are various means of either raising or maintaining those elements and there are pros and cons to each method. Without a full understanding of what is happening with the various elements from each means of maintenance, you will likely end up creating more trouble for yourself.
3) As Kris said "Nothing good happens fast in this hobby!" IMO, the nicest and most successful tanks are the ones that have significant elemental stability even if one or two of those elements are a bit off from what is deemed "ideal". I've seen many beautiful thriving reef tanks with a pH that runs 7.5 at night and 7.8 during the day. Could they be better if the pH was brought up? Maybe? I do know that if you take a tank that is thriving under specific stable parameters and shift those parameters quickly (even if it's a shift in the correct direction) there will likely be negative consequences. Change needs to happen slowly! Corals and fish can adapt to various conditions and water parameters, but significant fluctuations usually cause stress because the animals utilize metabolic energy to adapt (the level of stress and spent energy can be fatal if the changes are too drastic). Even though your trying to achieve a higher and generally more preferred pH level, if you went from a steady 8.0 to a steady 8.3 overnight then you would likley have some very stressed animals.
4) Learn and continue learning!! I read articles every day and learn something new from each and every one of them. This hobby has many rights, wrongs, and varying means of management that work or don't work for many people depending on 1,001 variables. Learn about chemistry. Learn about nutrients. Learn how your tank and animals respond to changes. Many of us can easily tell if "something" is up simply by looking at how the various animals look or are acting. That "something" can be as little as a minor pH shift, an accidental overdose of top off water, change in alk level, etc....
5) Ask why. Ask why your doing what your doing. When given advice or a suggestion, simply ask why. Do some research on the suggestions your given before you act. Don't just do something becuase others do it or becuase someone told you it will work for you. Many people are quick to say "I do this and so should you." There are many reasons why some practices will work for certain tanks and not for others. Asking "why" will help you determine what will work or not work for your situation. If your interested in trying a suggestion somone has given you then ask them to site a reference for their suggestion. There are thousands of articles (however - not all good) that people can site when providing a suggestion. If someone is suggesting something but can't show any evidence that it is an acceptable practice or show a study proving it's effects, then you may want to reconsider the legitimacy of that suggestion. Note that nearly each bit of significant advice I've given I also posted a link to a thread or article to show you I'm not just full of BS. People don't offer poor advice maliciously, but people often offer advice which may or may not be good not knowing themselves if their advice is good or not. In this hobby people try hard to help others, but often try too hard and that leads to misconceptions and myths being passed on as facts.
Nick. I don't mean any disrespect towards you at all. I very much understand your simple suggestion for "giving" it a try. What's the worst that could happen? The trouble is many of us know that it won't work and we're trying to save Heliguy the trouble, money, and frustration of trying yet another means of raising his pH when we know it won't do what your saying. Please, again, I mean no disrespect. I'm just debating the topic and with that debate I'm very much open to you showing me any legitimate research indicating that simply having crushed coral in a tank will maintain the pH your claiming.
I'd be more than happy to send anyone dozens of links to articles to learn from (and significantly improve your ability to maintain proper reef tank conditions). The reason I'm so adament about learning is because I spent thousands of dollars and killed dozens of animals before I took the time to learn a bit about the various aspects of the hobby to create a healthy environment. I'd rather not let others make the same mistake if I can prevent it. I feel pretty happy and confident in my ability to now maintain the health of some of the most delicate animals and I attribute it entirely to my desire to learn. The more you learn about reefing the more tools you have to create the most ideal conditions to house the animals you want to keep.
My calcium stays at 350+, I don't think that air signifigantly degrades lime water in short periods of time, or there is no CO2 in my house.:wink:
Wicked demon.
My response to your indication of skimming the crust off the top of the kalk was only to indicate that it wasn't necessary and would only degrade the effectiveness of the kalk. Just wanted you to know it was something you were doing that wasn't necessary. Regardless, even if you scrape the initial layer off the top, the kalk will continue to react with co2 in the air and continually create a new top layer of calcium carbonate. The article I posted indicates exactly as I'm stating. Again, I'm not just putting out some BS to waste everyones time. I'm trying to offer legitimate responses with literature to back my indications.
Jeremy