Help!! Alk wont go down....

Stop doing the daily water changes because you are just adding alk back into the tank

 

I wouldn't think 7.9 should stop you from starting your zeo. As long as your not much over 8 you should be fine. It's gonna take a bit before your tank hits ultra low nutrients.
Sounds like your water changes are doing a good job of keeping up with demand. Is your calcium and mag stable as well?

 

You would think so but many reefers do not realize that doing WC's stresses corals which in turn causes them to shutdown or slow their uptake/growth. It definitely sounds like this is happening!
Because reefers can't 'see' the corals' responses from WC's, they think everything is going on as usual. That is not the case! SPS's take at least 2 weeks and usually a lot longer to recover from any disruption/change...whether that be WC's, fragging, moving it, etc.... Stabilty is why there is such a need. How many times have we heard where reefers haven't done "anything" to their tanks and suddenly their corals are doing much better?! That's exactly why!! I still encourage you to leave things as is and give the corals time to adapt/adjust to the changes you have been making. You will then see the levels begin to drop.

 

I think the lowered water changes will help let your system use up the alk. Just be careful of it not getting too high when you start back up again

 

I know if I don't dose potassium weekly it depletes pretty fast.
Did the zeo guy say alk over 7.5 would bleach corals or cause burnt tips or both?

 

Cool. I should probably do some research anyway so you do have a bunch of questions about zeo on your alk thread.
What's suggested alk range for zeo? 6-7?

 

I used to run mine 9-9.5 but since spring trying 7.5-8.0 having very good results with coloration and growth. It seems all my problems with stn and overall sps health problems were when my tank would swing to about 10 dhk. I suppose cause I run pretty low nutrient system usually .02 to undetected po4 and 0 nitrate.
I know when my alk would near 10 it took 2 plus weeks to get 9 or less. But I don't do daily water changes. I do 10 percent every 5 days. And alk on new water runs 8dhk.
I read somewhere you can add some acid I think murat but not sure and that will lower dhk of you fresh saltwater barrel. It was on reef2reef somewhere.

 

The acid you 2 are referring to is Muratic Acid{Lowe's, H.D., Menards} That's what's used to 'cook' rocks or to basically burn/dissolve the top layer of rock off to rid it of nutrients/basically every and anything. I would never use it in my tanks because there are other ways to lower alk :0)

 

I wouldn't think that amount of water change (even the 2.5g daily) would really make a large difference in alk mathematically if there is a decent demand. How good is your test kit and reagents? Have any standard solutions you can reference off of? I would be more concerned with the lack of demand than the current levels. A decently stocked stony coral tank really should be dropping at least 1dkh/day if there is moderate growth and if heavily stocked with stony corals 3dkh drop isn't all that abnormal. My biocube would drop 3dkh and when I sold off the 120 livestock the 2 part plus kalk was around 2dkh/day drop.

I would worry more about trying to boost coral growth until the system is growing at least 1dkh/day if not more.

I was under the impression that zeo is really best used with mature colonies as ULNS tend to slow growth. I am sure zeo boards disagree with that, lol, but the concept of limiting nutrients and then tweaking levels to bring out different colors seems that it would not be best for growth, but would make cool colors.

 

Good to hear! The zero guys with growth feed small sps appropriate sized food? Back when I looked at zeo feeding wasn't all that popular.

What sort of alk consumption do the zeo guys with good growth have?