raising Ca in new salt mix

[JWClark]

Setting up a new tank (125g) and was going to go w/ tropic marin pro salt. goal is to eventually have a mixed tank w/ sps in a year or two.

Been thinking I might as well just use plain IO as it is about half the cost. My only concern is starting w/ the higher alk--but I imagine critters will take that down for me in time--and the lower Ca+. If I wanted to raise the Ca+ by 50ppm or so w/out raising alk would I just add an appropriate amount of CaCl at mixing time? I'm sure there are recipes so links are appreciated.

Don't think I'd need to raise mg+ levels from base IO but if I did I would just do the same as above w/ MgCl?

Guessing my targets for the tank would be about 450-480 Ca+, 8-9 dKH (but IO will start high), and 1350-1400 mg+ for the new set up.

Thanks.

[downbeach]

If you mix your salt mix to a SG of 1.026 (accurately) you shouldn't have to add anything. At that SG your Ca should be about 450 using IO, so no need to supplement.

[Randy Holmes-Farley]

If you mix your salt mix to a SG of 1.026 (accurately) you shouldn't have to add anything. At that SG your Ca should be about 450 using IO, so no need to supplement.


Are you thinking of Reef Crystals? Normal IO doesn't usually have calcium that high (unless they recently raised it). Last I saw the commercial target specs for IO, it was not that high.

For many years I added calcium chloride to IO and think it a fine plan if needed.

No need to worry about the alk. :)

[downbeach]

You're right it is IO RC, my bad.

[JWClark]

Used to use RC on my last tank (11 yrs ago). Back then sps were relatively new and I remember having issues w/ the few I got. From what I read it may have been the Alk that was my issue--I targeted high back then.

If I used RC do you think the high alk would be an issue? Based on the list here (posted in 09) RC has an alk of 13 as opposed to 11 for IO @ 35ppt.

Randy--was there a standard measure per volume you used when you added CaCl? Did you add dry to the fresh salt water mix?

[bertoni]

Most tanks should be okay with alkalinity at 13 dKH, although I'd probably target a lower level.

The old IO came at around 350 ppm, if my memory is correct, and I dosed it up to 400 ppm by adding calcium chloride to the freshly-mixed water. IO has changed its formulation, though, and the calcium level is higher now.

[Randy Holmes-Farley]

Randy--was there a standard measure per volume you used when you added CaCl? Did you add dry to the fresh salt water mix?

Yes and yes. I never measured anything, just added a fixed volume.

But now that they raised calcium somewhat, I only add magnesium (again, a fixed amount). I use limewater for calcium and alkalinity which tends to raise calcium long term, so I figure it balances out. :)

[JWClark]

So, according to the BRS calculator I only need to add around 100g CaCl to my total volume (150g+/-1or2) to raise the Ca 50ppm. I assumed starting was 400ppm for IO and desired was 450ppm. Does this sound in the ball park?

Could I fill the tank first then add the required CaCl or is it better to add as I mix batches? Would pre-dissolve in a few oz of RODI before adding. Will be mixing in Brute containers so not sure what the volumes will be per mix yet (I'm at Fort Lee right now so can't look at the size but they are the big ones at Lowes).

Anybody have current standard parameter measurements for IO vs RC? You'd think their website would have this info but I can't seem to find it. If Alk is the same I can just use RC and not worry about adding--but the high alk is my biggest worry.

[Randy Holmes-Farley]

That seems reasonable, yes.

You'd think their website would have this info but I can't seem to find it.

It is not something they provide publicly, probably because they want to avoid people with accurate or inaccurate kits from complaining it didn't meet the specs.

It is OK to put the calcium for a single batch or two into the new salt water, but perhaps not enough to boost the whole tank a lot because the calcium may get too high in the new salt water and begin to precipitate calcium carbonate.

[CDTReefer]

I agree with downbeach. I also use IO RC. Have used it for years and do water changes every 2-3 weeks. I never have and never will add supplements. I've seen and heard to any things go wrong with them. Yeah I do mostly softies, some sps not much.

[Randy Holmes-Farley]

Agree about what?

If you never need to add any alkalinity, you probably do not have much coralline algae in the tank.

Have you measured the alkalinity?

Most reef tanks cannot maintain alkalinity without supplements unless the water changes are huge (10-50% daily).

[JWClark]

Decided to go w/ plain IO to cycle the tank then adjust Ca and Mg levels to where I want before using kalk once things get going--should be good enough for my needs.

Is there any point in raising the Ca or Mg a little during the cycle? Will cycle w/ bioactiv8 (and starting some bio-pellets from the beginning). Will also add 30-60lbs of liverock for the process (will have another 100lbs or so of dry rock from reefcleaners in there).

[bertoni]

I wouldn't bother while the ammonia is still fairly high. There shouldn't be much consumption, anyway.

[Randy Holmes-Farley]

If you do a big water change after cycling (not all do), then it would likely be wasted anyway. :)