new auto topoff

[Sk8r]

...and I'm facing a trip of about a week, first time I've ever left this tank. My calcium demand for my 52 gal/10 gal sump is a little shy of 1/8th tsp Kent calcium supplement 3x weekly, and buffer dosing 2tsp 3x weekly on alternate days. I use ro/di water. Evaporation rate about 1/2 gallon a day.
This is a 2-3 month old tank with good coral growth for the few spses I have and I don't want to mess it up.
What I envision is adding enough calcium to the topoff water to have it come into the tank at 400, and just not worrying about the buffer for a week, because the calcium will be constantly replenished via the topoff water, right, so the topoff won't be dragging the buffer down?
Is that right thinking, or not?

 

[bertoni]

I would prefer to dose alkalinity in that situation, since it tends to get depleted more rapidly than calcium. They are consumed together in a fixed ratio,and seawater has a lot more "calcium" headroom.

 

[Randy Holmes-Farley]

I agree. Put the buffer in the top off as it drops much more on a percentage basis each day than does calcium. Just boost calcium to the high end (450 ppm or so) before you leave and it will be fine.

 

[Sk8r]

Thanks ever so much...I'd set up a competent tank sitter for all events and it turns out our 'sitter' is going with us on the trip. This auto topoff is my best fall-back, and I feel much better with the situation now, with good advice.

 

[Randy Holmes-Farley]

You're welcome.

Good luck.