Alkalinity question .....

[Straight.Reefin]

I have been doing this hobby for awhile now and cannot figure out why I can’t keep my alkalinity at about 8.8-9.1 range consistently??

I have 250 gallons of water

Parameters are

Calcium 420
Magnesium 1215-1300
Salinity- 1.026

Alkalinity just seems to always drop and can’t keep steady

For the last month I have tested religiously at the exact same time every day with my Hanna checker and it will not stay at the range I want

I have adjusted my bubble magus doser accordingly to see if my demand is more than I think but I’m up to 230 ml a day now of alk and I still can’t keep my alk at 8.8-9.1 range???

I have a bunch of coral but I would assume my corals would be growing insane with that high of a alk dosage but maybe I’m wrong???

The alk checker is calibrated also and within range...

If anyone could help me with some ideas or need some more information before helping just let me know!! Thanks!!!!

 

[EmdeReef]

What do you dose?
And what is your alk at? I assume you use a Hanna checker? Tried any other alk tests? Do you measure alk at the same time of the day? It’s generally normal for alk to vary 0.5-1dkh through the day depending on the time of the day unless dosing is timed so to offset swings, plus there are always possibilities for testing errors.

 

[hybridazn]

You would be amazed on how much 2 part is needed to sustain alk with the amount of water you have. I have a friend who has minimal corals but still has to dose over 300ml daily. Keep bumping it up until you get the level you want.

 

[Straight.Reefin]

What do you dose?
And what is your alk at? I assume you use a Hanna checker? Tried any other alk tests? Do you measure alk at the same time of the day? It’s generally normal for alk to vary 0.5-1dkh through the day depending on the time of the day unless dosing is timed so to offset swings, plus there are always possibilities for testing errors.

Thanks for the response!! Most of that info is in the above post...

I use Hanna checker

I test exact same time every day

Alk is 8.6 right now but was at 9.0 last night at the same exact time

As for trying other kits, I have tried salifert and it reads very similar

 

[jsker]

I am going back to what are you dosing?

Two part

Balling Method

Just Alk, Ca, Mg as needed

 

[Straight.Reefin]

I am going back to what are you dosing?

Bulk reef soda ash

 

[Straight.Reefin]

2 Cups per 1 gallon jug

 

[Straight.Reefin]

You would be amazed on how much 2 part is needed to sustain alk with the amount of water you have. I have a friend who has minimal corals but still has to dose over 300ml daily. Keep bumping it up until you get the level you want.

Really?!! And I have a bunch of coral and they are definitely growing....I have a ton of coraline also

 

[jsker]

as @hybridazn suggest bump up the dosing. I found with the more intervals I dose the steadier my alk stays

 

[Straight.Reefin]

as @hybridazn suggest bump up the dosing. I found with the more intervals I dose the steadier my alk stays

I forgot to say that, but I have been dosing every hour of the day all day and night long since day 1

I just can’t believe my tank is using 230 ml of alk but I guess it is what it is, I’ll bump it up 20 ml and see

 

[jsker]

I forgot to say that, but I have been dosing every hour of the day all day and night long since day 1

I just can’t believe my tank is using 230 ml of alk but I guess it is what it is, I’ll bump it up 20 ml and see

I have a small volume compared to yours at 80 gallons total water volume and I dose 40ml daily

 

[EmdeReef]

I have a small volume compared to yours at 80 gallons total water volume and I dose 40ml daily

I just looked at my doser and I’m at 55ml for my reefer 350 with only a bunch of frags...so I can definitely see you needing 300+

Maybe consider a calcium reactor (a chance for more gadgets)

 

[Straight.Reefin]

Thanks for checking your stuff and comparing for me!!! Makes me feel better about it for sure and maybe my system is just using a lot more than I thought it would

 

[jsker]

That is what R2R is about, ask the smallest of questions, and get advise and answers.

 

[EmdeReef]

Thanks for checking your stuff and comparing for me!!! Makes me feel better about it for sure and maybe my system is just using a lot more than I thought it would

It’s good news too: means corals are thriving in your tank!! (Maybe not financial good news, but then what is in this hobby

 

[Straight.Reefin]

It’s good news too: means corals are thriving in your tank!! (Maybe not financial good news, but then what is in this hobby

Hahaha for real! Thanks again everyone

 

[Iam.Will]

Night/Day PH swings? How are you getting dissolved oxygen into the tank? Could be using up your buffer to buffer. Just my bits.
Good luck

 

[Straight.Reefin]

Night/Day PH swings? How are you getting dissolved oxygen into the tank? Could be using up your buffer to buffer. Just my bits.
Good luck

Ph is kinda low and always is

Goes from about 8.0-8.2 all day and night

 

[EmdeReef]

Ph is kinda low and always is

Goes from about 8.0-8.2 all day and night

8-8.2 sounds pretty perfect IMO especially if stable in that range.

 

[Randy Holmes-Farley]

Folks can convert to something like dKH of alkalinity consumed per day to allow comparison between tanks. A calculator like this can be sued:

http://reef.diesyst.com/chemcalc/chem_calc3.html

In this case, at 230 mL per day of my DIY #1 (BRS) into 250 gallons is only 1.3 dKH per day.

That is not excessive for any reef tank. And the higher you maintain alkalinity, the higher the daily dose needs to be.

Even a soft coral tank can consume 2 dKH pr day of coralline growth is strong, and some of the demand in any tank is abiotic precipitation.