Soda ash vs bicarbonate for alk dosing
 

So I am a bit confused whether to use soda ash or bicarbonate for dosing. Read that soda ash slightly increases the ph while bicarbonate slightly decreases the ph. Mine stays around 8.0 to 8.2. Is a bit higher pH better than bit lower pH?

Advice please :)

I would use the soda hash. My Ph is about the same as yours and I use the BRS soda hash because I don't want my PH any lower than 8 if possible.

Yah that's what I was thinking too since I would prefer my pH to be above 8 instead of being below 8. Getting it from BRS is not possible for me so I will search local or else I will order that from RA. Thanks for the input :)

Agree about the soda ash. The majority of BRS users go with it rather than the bicarbonate.

Make your own from baking soda

Courtesy of Randy;
Spread baking soda (594 grams or about 2 ¼ cups) on a baking tray and heat in an ordinary oven at 300°F for one hour to drive off water and carbon dioxide. Overheating is not a problem, either with higher temperatures or longer times. Dissolve the residual solid in enough water to make 1 gallon total. This dissolution may require a fair amount of mixing. Warming it speeds dissolution. This solution will contain about 1,900 meq/L of alkalinity (5,300 dKH). I prefer to use baked baking soda rather than washing soda in this recipe as baking soda from a grocery store is always food grade, while washing soda may not have the same purity requirements. Arm & Hammer brand is a fine choice. Be sure to NOT use baking powder. Baking powder is a different material that often has phosphate as a main ingredient.

Yap but its too much hassle to save $30 :P Since my tank is small, one 4lb box should go for months. Manual preparation would have diminishing return for me :lol:

for the first couple of years that I was dosing I just baked baking soda in the oven. Cheap and easy. I baked like 3 large boxes worth and stored the result in zip loc bags. I tried soda ash recently and it was nice because it mixed a lot easier than baking soda. However, I ran out of it and kinda find it a pain to have to order more form BRS. Instead I just went to Superstore and bought more baking soda and baked it again. Anyway, I am using recipe #1 because my pH tends to be lower (7.9-8). If your pH tends to be higher you can use recipe #2 which doesn't involve baking.

Yah looks like most of the people use BRS stuff but I saw that RA is also selling the same stuff at a very reasonable price. Tempted by that.

Ya, it's good stuff. I just find it very pricy to keep ordering it and alk is a major consumable that adds up fast. It has been much more economical to just run to the supermarket to grab more alk :-) And I'm actually kinda used to mixing it now as I use a hand blender to mix the bicarbonate/baking soda.

I bake up baking soda for alk as well. Different view of what a hassle is I guress, waiting for something to come in the mail as opposed to spending an hour of so of my time baking. As far as pH, I don't recall the last time I even checked that paramater (edit: I checked a month or so ago when I was about to add two cleaner shrimp). Whenever I check alk, it seems to be chronically low, so I'll mix some baked baking soda into my water top off. The lps & few sps I have still seem to be able to get what they need to grow. I look at the tank every day & if there's a problem with paramaters, my critters will usually clue me in with odd behaviour. My BTAs are a very good indicator that something is amiss. Thankfully, there hasn't been any odd behaviour in a very long time.

Just order it from Eli at caco3reef.com

Thanks for the info. Didn't know he carried it.

I used to bake baking soda, but it was such a PITA to dissolve after wards. I considered trying to blend it back in to a powder to get it to dissolve better, but I was afraid of damaging the blender. I've been using straight baking soda since this tank was set up and it's gone swimmingly so far. I've never really tested pH though. Dissolves better if you add it to the hottest water you possibly can - hot water for baking soda (which is quickly cools), and icy cold water for calcium chloride, or it starts to boil. Chemistry is cool.

I was never good with chemistry other than mixing unknown stuffs and making tutti frutti :D

Bump for a question:

Alk and Ca are interrelated so I was wondering whether dosing Alk only will cause any sort of prob.....

of course dosing only for Alk will cause fluctuation in the rest of the tank's chemistry.
Not so much if you are only bringing the levels of Alk to par then start dosing all chemicals as to a recipe you will stick with and only adjust all levels accordingly to usage.

Since my mag (1380) and ca (440) remains within the desired value in between water changes, I was thinking of not touching them. Or should both Ca and Alk be dosed at the same time?

Ca and alk drop proportionately. For every degree of dKh you drop you lose about 20ppm Ca, they are simply combining in that proportion to produce Calcium Carbonate. It is possible your water changes are adding enough Ca but not enough alk to keep up, so you could just dose alk. Most of us have to dose Ca, alk and Mg in some ratio to each other to keep up between water changes.


Dan

no if you dose ca and alk when only alk is low both ca and alk will rise

i tried a product that contained ca mg str. it was terrible as only one would need to be brought up

bring your alk up and keep it up you may then see a steady decline in all three elements once kept in range and stable

So, for now, dosing alk should be fine. I will keep monitoring the big three and see how it changes.

Thanks everyone :)