The life of dolomite lime?

I was wondering how long the PH buffering effects of dolomite lime lasts. Does this stuff wear off after awhile? Do plants use it up as mag and calcium?
Does anyone add more to their soil during the life of their grow? Or after flushing?

The reason I ask is because my peat/perlite soil mix contains 2tbls. per gallon of mix. However, over the course of the last two months my soil PH has been becoming more acidic. I have flushed the soil; could this be a cause?

Thanks
-Ncogneato

Hey man thought i'd ring in here,

I've never had to add more over the course of the grow and at the rate your using you'll have plenty buffering capacity to get them through IMHO.
In organic grows flushing the soil is rough on the soil balance, it washes out alot of good stuff.
Over time the medium can acidify a bit but I find a ph of 6.5 in veg is good and I like it around 6.2 in flowering, not that I ever measure my soil ph because of the fact I make sure my plants get humic and fulvic acids in their teas, these also act as a soil buffer for your ph. Give it some time as it takes the microbes time to break down the lime after you flush the components that were broken down already.
Are you adjusting your water when you feed them? If using d lime use plain tap water ph ~7 which will up the soil ph a bit, if your lowering the water ph than that could compound the problem.

what's your feeding schedule like?

Peace
Sub's

Mine is a classic case of over reaction and lack of skill. I'm surprised my plants are still alive. I have had problems since the 6th week of veg. Starting with lower leaves and working it's way up throughout the whole plant. At first I thought I had a phosphorus deficiency, so I bumped up the guano. Then I thought I had a Mag deficiency due to excessive phosphorus so I flushed and added epsom salts at 1tblsp per gallon for 3 waterings. Even then I still had no luck. So I studied all the "sick plant" guides and came to a conclusion that I was deficient in potassium. I added liquid kelp and molasses along with a slight dose of fish emulsion and bat guano to even things out. After two weeks I still saw no improvement.The whole time my PH has been fluctuating high to low. I have a cheap ass Rapi-Test probe tester that I am sure is the source of most of my problems. This is where I made the dumbest newb mistake. I added 1cup of dolomite lime per gallon of water and watered it in to my pots. What a HUGE mistake. My PH skyrocked off the fcking charts. And so last night I spent all night flushing with gallons and gallons of PH'd water. After about 4 hours I finally got things back to about the 7.0 range, which I think is still a little too high. Then I watered in with 2tblsp vineger, 3tblsp quano and 1tblsp fish emulsion per gallon. My piece of shit PH meter now reads the soil at between 6.5 and 7.2. I just hope my girls can recover enough to produce a decent harvest. There is not one leaf that has not been affected by this torture. And to be honest I still don't know what the problem is.

HOLY SHIT!!!!

Stop right there, soil ph meters are the ABSOLUTE WORST wat of measuring soil ph as they are rarely accurate unless it a tool you paid 500$+ for.
I'm not very good with sick plants, you definately need to follow a more constant and balanced recipe, it sounds like your cocktailing your ingredients a little.
It doesn't matter what you feed them that is organic, the fact is if you don't have a healthy microbial system at work in your soil your plant will continue to starve for food.
Leave them be for awile, keep feeding plain water and let the soil mix do it's thing.

Soemtimes overmothering a plant can kill faster than a deficienty.

Sub