Should I dose?

I have a 20 long with a 10G sump/fuge, the tank has zoas, shrooms, rics, kenya tree, pulsing xenia and they are doing really well.

I recently added a a small monti cap and a digitata ($5 frag) because I wanted to see if they would grow. I am using an odyssea fixture (24W x 4 T5HO fixture) and changed the bulbs to wavepoint 12000K and actinics. The cap and digi are about 5" from the fixture.

I have never dosed before because there was never a demand for it so I was wondering if I should be dosing for these guys. I am doing 2 gallon changes every week and my Ca and alkalinity are ~460 and 8 respectively. Is this a suitable level for the sps that I have added? The Ca is likely alright for now but should I worry about the alk? I feel like the increased demand on Ca will be minimal and the water changed will be enough to maintain levels...is this an ok assumption?

They both seem to be doing alright, they are extended and looking happy after a week in the tank. The tip of the digi is white suggesting new growth.

Should I just leave it as is and see if the demand on Ca and alk increases as they grow?

Thanks!

 

if the salt you use has everthing you need, you may be ok, as long as you do the wc's

 

yeah I am pretty obsessive with the water changes

had a 10 gallon prior to this with only a hob, so i developed a good routine for WC's. If the Ca and Alk stay relatively stable though will they be ok? Is my alk a little low?

 

Your alk is fine. Mine has been way way lower than that, for a while. I have several monti caps and a digi and many other species of sps. Welcome to the club lol. See how they do and adjust if necessary. If you see new growth then you are doing somethin right!

 

thanks, yeah everything seems to be doing well. My Ca dropped from 480 to 440 over the week and a 10% WC brought it back up. The alk didn't change noticeably over the week.

So I think I am ok for dosing for now.

 

Don't let your alk drop below 7 and keep your Ca above 380. Test weekly and keep a journal of your results so you can see any trends. As the Montis get bigger they will place a larger and larger demand as the grow.

 

+1 on above
and I would double check your test results

becuase a 40ppm increase on Ca as a result of a 10% water change seems a bit much to me - mathmatically

additionally - if you did in fact suffer a swing/ drop of 40ppm calcium per week then that would be the right time to start dosing
whilst both levels mentioned stayed within acceptable tolerance for running a reef tank
it would be better to replace to compensate for 6ppm calcium per day , than to add enough once per week to compensate for a 40ppm drop

Stee

 

Thanks for the advice John.

I have been keeping a log of all my tests since I added the sps. I didn't keep one before because I only tested very periodically.

Steve:

Good points, I thought it might be a little big of an increase in Ca with only 2 gallons of new water. I will test again this weekend to see. My test kit is a little vague on the exact moment that it changes color unfortunately (fyi Both the alk and Ca are api test kits). It turns a bluish purple first and then goes to blue with 1-2 more drops, so unfortunately this leads to some uncertainty. I think I am going to have to develop a consistent method for determining what the ppm is.

 

Hi tharsis

my opinion

390 , 410, 420, 440, - they are all just numbers and none of them are any better than any other
the trick is stability - if you pick 420 , and keep it stable at 420 , replacing what is utilised , then your corals will do just as well in that as they would had you chosen 440
same with Alk/ DKH as Gabby mentions , if your at 8, keep it at 8, replace what is utilised regular, then 8 is fine IME

suggestion
test a batch of the new salt water you make at next water test , and add those extra drops to get the full blue in test tube see what level your new salt water is at
if you then aim to keep your reef tank ca level the same as that, then the 10% water changes each week, will have very similar parameters as your tank water and you eliminate the peaks and troughs, and improve stability for the corals

Steve

 

great advice, I like your suggestion.