How to raise/maintain alk using soda ash

[GHOSTLY]

Im currently baking some baking soda to raise my heavily sps stocked reef tanks alkalinity up

I dose around 3ml of AFR liquid every day but haven't tested in so long.

Today's test 7pm
Mg 1480
Calcium 450
Phosphate 0.08
Nitrate 5-10
Alk 5.5

My alk is definitely too low. I was told the best way to raise alkalinity (and ph) was to dose soda ash but I keep getting ratios that are too big for my tank. Anyone know some good ratios and amounts to dose (preferably in ML) to raise my alk around. 2 a day up to 7.5dkh

 

[GHOSTLY]

Im currently baking some baking soda to raise my heavily sps stocked reef tanks alkalinity up

I dose around 3ml of AFR liquid every day but haven't tested in so long.

Today's test 7pm
Mg 1480
Calcium 450
Phosphate 0.08
Nitrate 5-10
Alk 5.5

My alk is definitely too low. I was told the best way to raise alkalinity (and ph) was to dose soda ash but I keep getting ratios that are too big for my tank. Anyone know some good ratios and amounts to dose (preferably in ML) to raise my alk around. 2 a day up to 7.5dkh

Wanting to mix in 500ml of water

 

[ReneReef]

Just use the baking soda.
Besides KH, soda ash also increases pH, during large KH correction that is not an ideal combo. pH may go to high. And an incidental pH increase it will not last anyway.

If you want to increase pH with soda ash, you would need to switch from AFR to a soda ash based product.

 

[GHOSTLY]

Just use the baking soda.
Besides KH, soda ash also increases pH, during large KH correction that is not an ideal combo. pH may go to high. And an incidental pH increase it will not last anyway.

If you want to increase pH with soda ash, you would need to switch from AFR to a soda ash based product.

I just ran my test for my dkh consumption
Yesterday
6pm 5.5
After dosing 3ML AFR
1030 5.7

Today 540pm
4.5
Im experiencing about a full dkh drop daily

 

[GHOSTLY]

Should I be adding this amount of fluids daily (spanned throughout the day) or broken up

 

[Randy Holmes-Farley Verified Community Expert]

There’s no way to know except by trial and error how
much it takes to maintain alk. The daily drop at 5 dKH is much lower than it will be at 8 dKH.

I’d personally just up the AFR slowly to meet your target. But using baking soda to boost alk to 7 dKH over 3 days and then upping the AFR to keep it there is also a sound plan.

 

[ReneReef]

I just ran my test for my dkh consumption
Yesterday
6pm 5.5
After dosing 3ML AFR
1030 5.7

Today 540pm
4.5
Im experiencing about a full dkh drop daily

I don't think that is a good way to measure consumption.
Not with any additive, but especially AFR. This is because the KH release from AFR is not instant. It takes an unknown amount of time.

From your tank thread I gather that you have a 20 gallon AIO tank. Correct?
Assuming a net system volume of about 17 gallons (~65 Liter). 3 mL of AFR will dose about 0.28 KH.
The 1 KH consumption on top of the 3mL dose is therefore unlikely to be correct.

As Randy mentioned there are 2 ways to go about it, slowly increase the AFR dose or add bicarb over serval days and stabilize after that with AFR.

In case of the first option. I would increase the AFR dose to 4 mL a day and take a week before evaluating.
Be precise: measure your KH at day one and day seven at the same time of day, before dosing AFR. Dose AFR at the same time every day. This way you allow things to stabilize as much as possible and make measurement as comparable as possible.

If you want to increase KH with bicarb you are going to need about 3,9 grams to increase KH by 2, assuming the ~17 gallons net system volume. You can dissolve the bicarb in at bit of RO-water (50-100mL is enough) and dose over 2-3 days.
After this correction, start dosing a bit more AFR (3.5 of 4 mL a day I would think) and follow the KH trend over a week as I described earlier.

As general take-away: adjust dosage to trends, not single measurement or one day events.

 

[BryanM]

I’d personally just up the AFR slowly to meet your target. But using baking soda to boost alk to 7 dKH over 3 days and then upping the AFR to keep it there is also a sound plan.

Do this that Randy said. This is an excellent plan of action.

 

[GHOSTLY]

There’s no way to know except by trial and error how
much it takes to maintain alk. The daily drop at 5 dKH is much lower than it will be at 8 dKH.

I’d personally just up the AFR slowly to meet your target. But using baking soda to boost alk to 7 dKH over 3 days and then upping the AFR to keep it there is also a sound plan.

Im trying to raise it right now but im thinking ill need to up my soda ash/afr dosage

Just in rh its dropped .4dkh despite dosing soda and afr. I believe im dropping 1dkh a day which means I need to up my dosage. I dose by hand so ive been trying to spread 5ml a day to 3 batches. Any tips on what to do to maintain or is it also trial/error