My Alk is in the basement (1.7meq)

[fishfarmer]

Hi all,

I've been getting a consistantly low alkalinity reading since July 2. I've done 8 tests(Salifert) since then. All have been 1.17 to 2.06 meq/L. I've ruled out a bad test kit by testing a different tank and testing fresh mixed seawater(Kent salt gave 2.97).

Calcium = 413 ppm
pH = 8.2

I dose kalk 24/7 via a gravity/vacuum water bottle. In the spring I started using garden hydrated lime instead of the reef grade kalk. I didn't notice much change in my readings. Sometimes I use AragaMIGHT which does lower my alk, but I usually can bring it back with kalk.

My alk was a little on the high side in May. Readings were 4.66 and 5.4. They were running 2.6 to 3.3 before this.

FWIW my corals don't seen affected at all, my xenias still pulse and coralline needs constant scraping. My tank specs are at the bottom if you need more info. How do I get it back up or should I bother since nothing seems to be affected by it?

 

[Anonymous]

fishfarmer, organic acids produced via bacterial activity or general "system" metabolism could be, through continual degradation, causing your concentrations of buffering ions to dissappear as they are used towards neutralization reactions in the presence of acidic compounds/hydronium ions. I'd do a big water change, and see what happens. Your 2.6-3.3 meq/L readings are generally ideal. I think a decent size water change would really help this situation. I would do something to correct the situation, because a lack of adequate alkalintiy has effect on other conditions (like the concentration of metabolic/organic acids) that will definitely degrade the optimum biological function of your flora/fauna.

 

[DennisL]

I would try dosing one of the buffering compounds. Something like Kent Superbuffer dKH or Pro Buffer. I've used regular baking soda, but some people say it doesn't have all the right stuff.

 

[Plato1]

I'd do what galleon said and change around 20%. I recommend doing this for consecutive water changes. Also, if you want to boost the alk with a powder use the seachem alk buffer because it doesn't affect pH in my experience. For what it's worth, don't sweat it too much since everything in the tank is OK (appearance wise). 1.7 is a bit low and should be corrected, and will with the water changes and addition of buffer (but don't expect overnight). I'm sure I'm telling you stuff you already know. Anyway, I hope this helps.

PS- I try to stay away from Kent products as they are notoriously diluted.

 

[BReefCase]

The one product that unfailingly raises Alkalinity for me (on the rare occassions that dripping Calcium Hydroxide doesn't balance everything ionically) is Kent's Superbuffer dKH. I recommend Kent's because by following their label directions, you can know almost precisely how much your Alk will rise per dose, without having to guess how much to use.

For that matter, now that I think about it I use a number of Kent products with complete satisfaction. (And no, I don't sell or work for Kent's.)