How Big is Your System (Really)?

[Joe.D]

While it would have been smart to measure how many gallons were put in when setting up - I did not have that option as my LFS did the set up and filled from the tank in their truck.

That said, I tried to look at total system volume and then used online calculators based on the weight of rock and sand that were added. I’ve dosed from there - which, I’d think gets you in the ballpark without causing issues. Then, I adjusted dosing until I got parameters to what I was looking for.

I also started on the low side of dosing recommendations. Figured it’s kinda like salting your food - you can always add more, not so easy to reduce once it’s there.

 

[Hooz]

I only have smaller AiO tanks, so it was easy to just fill them initially with measured buckets. My IM 10 holds 7 gallons, my IM 30L holds 21 gallons, etc, etc.

 

[McPuff]

I've got a 300DD with a 75 gal plumbed in, an 80 gal sump (1/2 full), and a 10 gal refugium. All my calculations assume 300 gallons of water (total) and that seems to work well.

 

[Laith]

This is the way I did it:

I took one liter of RO/DI water and measured how much of the salt I use would bring that liter of water to 1.0262.

Then when I filled my tank (theoretical volume of about 1900 liters) after all the aquascape, sand and equipment was in, I measured how many kilos of salt it took to bring the whole thing to 1.0262. Divide the number of kilos by the amount of salt required to bring one liter to 1.0262 gave me a pretty accurate net volume of water in the tank.

Of course that was in October of 2019 and the the coral growth has probably reduced the total volume so now I just guess more or less how much the coral is now displacing...

 

[Reefering1]

One time I accidentally dosed 222ml of alk supplement. Dkh jumped however much, I then played around with the brs dosing calculator to figure out that my sys is 601L actual running volume. Then I dosed 222ml of Ca supplement to balance at new levels, then let it come back down naturally. Moral of the story is that the dosing calculator can tell you exact volume