ALK drop in 18 hours....

[Rskiba]

I dosed 2 part about 3 PM yesterday and the graph shows the rise in ALK to 8.23 when the Trident test occurred at 6 PM. Since then the ALK has been declining to now 7.65 in 18 hours. The tank is new - 6 weeks in and has one fish, and about 15 very small coral frags that are doing quite well. They consist of Mushrooms, Zoas, single Favia, Green Start Polyp and a Duncan. Nothing is larger than a frag plug. Tank volume is 145 gallons including sump.

Is this decline "normal"? It has been relatively consistent day after day for the last 10. I have a bit of brown and green algae, but very little and the CUC which has been in place for 2 weeks is handling that well. I feel like the tank has very little load on it and this seems excessive to me but I don't want to go with my feelings and rather use facts.

 

[shakacuz]

did you dose close to the probe?

 

[Crustaceon]

What's your PH at? Also, if you're dosing soda ash, don't dump all of it in at once to make the big cloud in the display. Pour it in a fine stream directly into a circulation pump. It really needs to be gradually introduced into a very high flow area otherwise there's a good chance it'll precipitate. I had a return line that was 1/2 clogged with precipitate on a system that couldn't maintain alkalinity on until I took the lines apart and realized why.

 

[Rskiba]

PH is 8.1 and the dosing was done in the Display. Probes are in the sump. My dosing is manual at this point in time,

 

[Rskiba]

When I said above it has been consistent, I mean that I see this same declining pattern everyday like the tank is using the ALK but I don't think there is enough load to create that result.

 

[Rskiba]

What's your PH at? Also, if you're dosing soda ash, don't dump all of it in at once to make the big cloud in the display. Pour it in a fine stream directly into a circulation pump. It really needs to be gradually introduced into a very high flow area otherwise there's a good chance it'll precipitate. I had a return line that was 1/2 clogged with precipitate on a system that couldn't maintain alkalinity on until I took the lines apart and realized why.

I always add a small amount of soda ash in a fine stream and wait for the cloud to disappear. It may take me 15 minutes to DOS 1.5oz - lol. This is why I want to get this straight so I can add my DOS units to handle this function.

 

[StatelineReefer]

Full tank shot please. Also, why are you dosing?

 

[Cjeippert]

Try a salifert test kit, my trident is always doing crazy things. I use hanna, salifert, and trident for alk and cal testing. Trident always falls way low, hanna is high, and salifert in the middle. It might need some settling in time if new

 

[Cjeippert]

Try a salifert test kit, my trident is always doing crazy things. I use hanna, salifert, and trident for alk and cal testing. Trident always falls way low, hanna is high, and salifert in the middle.

DOS are awesome for alk and cal, but very loud for kalk and water changs due to speed the stepper motors need to turn

 

[Rskiba]

Also, why are you dosing?

I was trying to keep my water parameters even and not up and down during water changes. I don't understand how the ALK would fall so much with so little load. The test value might be off but I would expect it to be relative to each other. Regardless what the test number is, it still showing a decline in ALK. I have no local club or LFS to ask for help, so R2R is my source!

 

[Rskiba]

DOS are awesome for alk and cal, but very loud for kalk and water changs due to speed the stepper motors need to turn

Thanks Cjeippert, but not using any DOS units at this time.

 

[StatelineReefer]

I was trying to keep my water parameters even and not up and down during water changes. I don't understand how the ALK would fall so much with so little load. The test value might be off but I would expect it to be relative to each other. Regardless what the test number is, it still showing a decline in ALK. I have no local club or LFS to ask for help, so R2R is my source!

Because it likely precipitated.

What are your 'big four' parameters today...

PH
Alk
Cal
Mag

 

[Rskiba]

 

[Rskiba]

PH 8.1
Alk 7.6
Cal 452
Mag 1395

 

[Rskiba]

If it precipitated, wouldn't that be visible in the tank?

 

[StatelineReefer]

If it precipitated, wouldn't that be visible in the tank?

Not immediately or necessarily, no more than adding a few grains of sand.

Which calculator did you end up using for determining your dose?

 

[TheReefDiary]

I dosed 2 part about 3 PM yesterday and the graph shows the rise in ALK to 8.23 when the Trident test occurred at 6 PM. Since then the ALK has been declining to now 7.65 in 18 hours. The tank is new - 6 weeks in and has one fish, and about 15 very small coral frags that are doing quite well. They consist of Mushrooms, Zoas, single Favia, Green Start Polyp and a Duncan. Nothing is larger than a frag plug. Tank volume is 145 gallons including sump.

Is this decline "normal"? It has been relatively consistent day after day for the last 10. I have a bit of brown and green algae, but very little and the CUC which has been in place for 2 weeks is handling that well. I feel like the tank has very little load on it and this seems excessive to me but I don't want to go with my feelings and rather use facts.

I've been having similar issues. I dose ask in the evening when I get home and my alk is around 7.8. after dosing at night I get it back up to 8.2-8.3 for it to all be used up the next day. My tank is only 13.5g. Don't have the space for a doser currently otherwise I would be dosing throughout the day.

Still perplexed as to how my system is using so much.

 

[Rskiba]

Not immediately or necessarily, no more than adding a few grains of sand.

Which calculator did you end up using for determining your dose?

BRS calculators.

 

[StatelineReefer]

I would add steadily and slowly, calculate towards not exceeding a half dkh rise over 24 hours, this will lessen the chance of precipitation while still allowing for the maintenance level you're looking for.

What are the mixed parameters of the salt you're using, the math would put it at Red Sea Blue Bucket (8.5 DKH, 430-435 cal, 1350 mag mixed at 1.026sg).

As far as determining your alkalinity drop, theres a lot of factors that could be at , this scenario points more toward carbonic acid involvement than coral uptake. There are only two skeletonizing corals you mention, a favia and a duncan.

 

[Rskiba]

I am going to do a water change tonight. Should I test tomorrow and not dose anything for a week and then test again?