Another Apex chart and starting two part with BRS

[lilbitreefer]

I've been playing with the charts on Apex and found a good way to start two part dosing and and a chart to show it. So I bought some stony corals. Mainly a few LPS. I started checking Alk and Ca at night I then dosed it according to BRS calculator. I went off of what the Alk recomedation for dosing was. The first two days you can see a huge spike in Alk. The next three day you can see lower and lower spikes. This is because I was reaching my target dKH of 9. Once I noticed my dKH remaining steady I switched to a morning dosing and testing schedule. Below is a chart of my Alk and how much I dosed.
Ok, the reason for the initial testing and dosig in the evening. Besides it working out well for my work schedule, I thought it would be a bit more gentler way of increasing the dKH over the next few days. I theorised the dKH corrolates with pH and it would be the highest at the end of the day. Thus, needing a lower amount of Alk. According to the BRS website I only raised the Alk no more than 1.4dKH a day. By today I found I was dosing right on par with the BRS recomndation of 0.1mL/ gallon of tank water.

Date Time Alk Ak/Ca dosed
11-Nov 2300 6.66 124mL
12-Nov 1730 7.78 113mL
13-Nov 1730 8.79 19.5mL
14-Nov 0800 8.9 9.1mL
15-Nov 0814 8.85 13.9mL

Results:
From the first day of dosing my corals have started to open up. They appear happy and healthy at this time. I hav enoticed that they are remaining open at night. My BTA and Zoa still closed up at night. Is this normal? Any thoughts? Should I increase my target dKH?

 

[lilbitreefer]

Some extra info. I have been testing with the Hanna Alk digital kit. My tank is a 120g mixed reef. Running zeovit and small refugium currently holding nuisance algae (until FL can recover their supply of chaeto after the hurricane). The LFS has yet to get in a shipment from their seller in FL.
And if BRS is reading this please get some Hanna Alk reagent in stock. I am running low and would like to continue these testing to show others. Thanks

 

[Randy Holmes-Farley]

Thanks for showing the data.

Here's my blurb recommendation on alkalinity targets copied from an article:

Unlike the calcium concentration, it is widely believed that certain organisms calcify more quickly at alkalinity levels higher than those in normal seawater. This result has also been demonstrated in the scientific literature, which has shown that adding bicarbonate to seawater increases the rate of calcification in some corals. Uptake of bicarbonate can consequently become rate limiting in many corals. This may be partly due to the fact that the external bicarbonate concentration is not large to begin with (relative to, for example, the calcium concentration, which is effectively about 5 times higher).

For these reasons, alkalinity maintenance is a critical aspect of coral reef aquarium husbandry. In the absence of supplementation, alkalinity will rapidly drop as corals use up much of what is present in seawater. Water changes are not usually sufficient to maintain alkalinity unless there is very little calcification taking place. Most reef aquarists try to maintain alkalinity at levels at or slightly above those of normal seawater, although exactly what levels different aquarists target depends a bit on the goals of their aquaria.

Interestingly, because some corals may calcify faster at higher alkalinity levels, and because the abiotic (nonbiological) precipitation of calcium carbonate on heaters and pumps also rises as alkalinity rises, the demand for alkalinity (and calcium) rises as the alkalinity rises. So an aquarist generally must dose more calcium and alkalinity EVERY DAY to maintain a higher alkalinity (say, 11 dKH) than to maintain 7 dKH. It is not just a one-time boost that is needed to make up that difference. In fact, calcification gets so slow as the alkalinity drops below 6 dKH that reef aquaria rarely get much below that point, even with no dosing: natural calcification has nearly stopped at that level.

In general, I suggest that aquarists maintain alkalinity between about 7-11 dKH (2.5 and 4 meq/L; 125-200 ppm CaCO3 equivalents). Many aquarists growing SPS corals and using Ultra Low Nutrient Systems (ULNS) have found that the corals suffer from "burnt tips" if the alkalinity is too high or changes too much. It is not at all clear why this is the case, but such aquaria are better served by alkalinity in the 7-8 dKH range.
As mentioned above, alkalinity levels above those in natural seawater increase the abiotic precipitation of calcium carbonate on warm objects such as heaters and pump impellers, or sometimes even in sand beds. This precipitation not only wastes calcium and alkalinity that aquarists are carefully adding, but it also increases equipment maintenance requirements and can “damage†a sand bed, hardening it into a chunk of limestone. When elevated alkalinity is driving this precipitation, it can also depress the calcium level. An excessively high alkalinity level can therefore create undesirable consequences.

I suggest that aquarists use a balanced calcium and alkalinity additive system of some sort for routine maintenance. The most popular of these balanced methods include limewater (kalkwasser), calcium carbonate/carbon dioxide reactors, and the two-part/three part additive systems.

For rapid alkalinity corrections, aquarists can simply use baking soda (sodium bicarbonate) or washing soda (sodium carbonate; baked baking soda) to good effect. The latter raises pH as well as alkalinity while the former has a very small pH lowering effect. Mixtures can also be used, and are what many hobby chemical supply companies sell as “buffersâ€. Most often, sodium carbonate is preferred, however, since most tanks can be helped by a pH boost.

 

[Randy Holmes-Farley]

Some extra info. I have been testing with the Hanna Alk digital kit. My tank is a 120g mixed reef. Running zeovit and small refugium currently holding nuisance algae (until FL can recover their supply of chaeto after the hurricane). The LFS has yet to get in a shipment from their seller in FL.
And if BRS is reading this please get some Hanna Alk reagent in stock. I am running low and would like to continue these testing to show others. Thanks

If you are driving nutrients very low with the zeovit system, I'd suggest a target alkalinity level of 7-8 dKH.

 

[lilbitreefer]

Forgot to mention I have been dosing the Ca in equal amounts as well.