There may not be a good answer to this question post setup of a tank but how does one figure out displacement?
I've been trying to figure out my total water volume as I've been gearing up to dose BRS 2-part. I have a 90 gallon with a 30 gal sump and lots of rock but I have no idea how to figure out its displacement.
I've heard people mention weight of rock but what would that have to do with it? If I place a sealed "orb" or something that weighs next to nothing in a tank along side a rock of equal mass they're displacing equally aren't they?
Amazing explanationDosing is based on individual tank consumption. There is no straight forward amount to dose. But, There is however a few ways to find out consumption. (Consumption will change as corals grow)
First and foremost, Grab yourself a set of reliable test kits and a Calibrated refractometer. [this is so important]
Check your aquarium water a few times. Write down your results each time and take your time when doing it, after a while it becomes a breeze. Some people are confused when they are testing, and i believe the more you test, the easier getting accurate results will become.
If your levels are within target range [Salinity,Alkalinity,Calcium,& Magnesium] - then you are ready to start testing for consumption.
Note, If either ALK,CAL,MAG, or salinity is out of whack you will need to manually fix them before starting. [via water change or dosing] When manually fixing, always remember slower is better. Take your time and get a grip on what needs to be done before taking action.
Now, With a mixed reef generally things are much easier since consumption is generally low, Once your levels are in check you can simply test - write down results, then test again 7 days later to find a weekly consumption. Which you will then need to divide by 7 to find your daily consumption. [Repeat this for a few weeks]
With a heavily stocked tank/ SPS tank it can be a little challenging because of swings, You can avoid any possible swings by testing every 24 hours and manually dosing if needed. Just record everything so you can look back when needed.
Another option that kind of goes with the above is to actively test and start with a low daily dose and adjust. Some recommend 10ml of ALK/CAL - increase/decrease as needed.
You should really be on top of testing for the first couple of months IMO. Once you get the hang of it, you can easily test everything in under 5 minutes.
When setting up the doser- Run the doser with regular RO/DI water to test its accuracy. This is very important because some will under/over dose and you will need to adjust before automating. Don't believe that it should be accurate because it cost 300$
-When using an automated doser [ie bubble magus] I suggest splitting the automated dose into 3 or 4 times a day.
Some people get very nervous with dosing, Just know if your using ESV you will generally only need to dose 2 parts daily since mag is covered within the Bionic 2 part. With the BRS kits you will need to dose all three individually [brs is much less potent and requires higher amounts of dosing].
If you decide to use ESV BIONIC and actually read the bottle you will realize the following [actual water volume]
That 1 ml per gallon of [ALK] will raise your ALK by roughly 2.07 dkh.
That 1 ml per gallon of [CAL] will raise your cal 15ppt.
For example, if you have a 100 gallon tank you will need to dose the following.
100 ml of alk to raise approximately dkh 2.07
100 ml of cal to raise your cal approximately 15ppt
I believe dosing is actually forgiving to a certain point. If you sit back and realize how much you actually need to dose to increase levels unsafely then you are ahead of most already.
[ALWAYS FIGURE OUT YOUR TOTAL WATER VOLUME INCLUDING DISPLACEMENT]
If you dose 25 ml on a 100gallon tank [actual water volume]
ALK will raise: approx .5 DKH
CAL will raise: approx 3.75 ppt
If you dose 50 ml on a 100gallon tank [actual water volume]
ALK will raise: approx 1 DKH
CAL will raise: approx 7.5 ppt
You can figure out
ALK 2.07 dkh DIVIDED by the amount of gallons, Then multiply that number by the amount you wish to dose in [ML] for the result
CAL 15 ppt DIVIDED by the amount of gallons, Then multiply that number by the amount you wish to dose in [ML] for the result
When raising or adjusting levels it's best split into multiple doses when possible. You also need to wait around 5 minutes between Dosing ALK/CAL to avoid any precipitation. When dosing 2 part you need to actively perform at least 20% water changes to remove any excess chemicals/buildup. Realize that 2 part in large amounts will raise your salinity.
Once you have your consumption dialed in you should generally start by dosing equal parts of both ALK and CAL, Most of the time a reef will require equal parts of both. In some cases with excessively large caps or heavy coraline algae your usage may vary and adjustments will need to be made. It isn't a bad sign If your aquarium requires different amounts of alk/cal, just understand why.