Consumption rate of Cal/Alk on BIG SPS Tanks?

[CuzzA]

I'm in the planning/building stages of a 300 gallon system with a 40 gallon prop tank. This will be a mixed reef, but heavy on the sps.

I'm curious what kind of consumption of cal and alk do you guys see with your tanks? I'll likely dose first, so I'm curious as frags turn to small colonies how much 2 part are you using per month? What size dosing containers? I may build my own with some spare acrylic I have laying around. But I don't want to be filling containers every week. Monthly would be more reasonable. So I want to get the size right if I'm going to take the time to make the containers. Of course eventually I'll probably setup a cal reactor, but for now I'm choosing to dose. I'll be dosing kalk through my ATO as well.

Thanks.

 

[Raoul5Duke]

I have a ~360 gallon DT, 40 gallon actual water sump (80 total) & 40 frag grow out plumbed together. I am currently dosing 200ml daily of CA & ALK, actual consumption is likely slightly lower as I am still dialing it in. I found some very reasonably priced 1 gallon acrylic dosing containers on E-bay. At that rate I am likely filling them every 2 weeks. I am thinking about adding a Kalk reactor at some point but I have always liked the ease and controllability of 2 part dosing even if the expense is higher.

 

[CuzzA]

Hmm. I was thinking of making the containers ~4 liters/1 gallon. I'm wondering if I should maybe double that size.

My system will be a 300 gallon display, 80 gallon sump (40 actual volume), 20 gallon rdsb, 20 gallon cryptic fuge, 40 breeder prop tank. So a total system volume of 420 gallons. Boy that's a lot of water!!!

 

[iced98lx]

Thought about a calcium reactor at that size?

 

[CuzzA]

Yes. I Thought about it and have allocated the space to add one in the future. I just figured it would be quite a while before I would need one for a couple reasons.

1) Most of the corals in my 90 are only small colonies or frags, of course I'll be adding a lot more once I have this system setup. But for now I'm still able to replenish through kalk and water changes. I hope to just start to supplement through dosing with Randy's recipe. Which I believe would get me by for pretty cheap for a long while.

2) In my fish closet I'll have a 100 gallon automatic batch water changer that will replace 3 gallons per day of natural sea water collected and filtered by de, carbon and uv. Benefits of living next to the water here in Florida. So yet another source of replenishing.

And as I'm sure you guys know big tanks are big money. So if I can hold off on something like a calcium reactor for a while and focus on actually acquiring nice small colonies I'd like to go that route. Who knows though, I may change my mind. Just trying to figure out things to build with all this spare would and acrylic.

 

[iced98lx]

Yea, nice you're doing what my next suggestion was "Kalk and water changes until you step into the CaRx"

I will say while I see the point, if you're off to buy dosing pumps etc, everyone who runs a big tank with a Calcium Reactor seems to swear by them. The money, well, clearly we're all loopy for spending what we do.

It's all about levels, pick what you want to be at, if start small and work up to it dose wise, then figure out your maintain dose, which naturally will go up with lots of small colonies/frags over time. Wish I had better input on the original questions (how much 2 part do you go through) but I'm still just using Kalk and will jump strait to a CaRx when the time comes.

 

[Raoul5Duke]

As iced suggested the CaRx has proven to be the most cost effective over time. There was an article in Reefkeeping where, I believe Randy Holmes Farley discussed the benefits of each, etc. There is a thread over in the SPS only forum or maybe here in the Large Tank forum where some with large tanks have gone back to 2 part dosing and claim they get better growth & colors with 2 part. I can't really confirm that, but an interesting read. The auto water change is great, I have a genesis system on my tank and it was probably the best piece of equipment I added on a large tank. Push a couple of buttons and water changes are done. Makes maintenance easy and gives you a failsafe if something is off, you can just do a big water change to get things back in order.