I have a Solana 34g ( six months) and something is not right. Parameters are all within range albeit, I can't seem to bring down the alkalinity and calcium has been difficult to raise. Moderate Coraline growth.

Solana 34g
NEP Light 9 Hour cycle
Stock Skimmer
No bioballs
Purapad in second chamber
Weekly 5 gallon water changes
Extreme Typhoon RO/DI
Reef Crystals

Bioload:
Mated Maroons
Cleaner Shrimp
Emerald Crab
Assorted hermits and snails

Corals:
Frogspawn was 6" across and very happy, now opens maybe to 2"
Hammer was 5" across now opens to an inch and lost two heads
Candy Canes used to be full and plump now tight and half open
Xenia's from Biocube29g grew awesome with intense pulsing: two months in the Solana barley pulse and no further growth.
Red Sea Xenia went from white to brown placed mid tank
Ricordeas split and do great


Parameters:
Ammonia 0
Nitrates 5
Alkalinity 12
Calcium 410
Mag 1280
Phos 0

The corals are telling the story but the parameters aren't giving any insight. I am dosing but would ask for suggestions: maybe I am going about it wrong.

I am at a loss: Is it possible to overskim?

could your bulb be old, ready for replacement? I dont like your alk that high...If your test kit is off, your alk could be even higher and you wouldnt know it...

you using a 2-part solution>?

Skimmer wouldnt be the problem...

id get another test kit or take it to the LFS and have them compare their results to ur test kit. you could br grossly overdosing ur tank. in th emean time do a 20% water change and see if you notice improvement, also decrease/stop dosing until you know the problem

yeah, I'm thinking your alk is at 14-15 or something....which would explain everything....

Your alk is too high, stops ca utilization by inverts. The ca is there but the corals can't use it. Stop dosing and do regular water changes. Overskmming is possible with like an ev-120 on a fishless 10g but is the last thing hobbyists will ever do. It is an old wives tale spread by people who are too tight to buy one. Non photosynthetic gorgonians are about the only exception I can think of where a skimmer will reduce growth. You would not have any detectable nitrates if you were skimming too much anyway.

I did exactly as you say. Took sample water to LFS and the readings I posted are the results.

I have completed stopped dosing two part or any dkh and only dosing Mag and Calcium in an effort to bring them up. My understanding is that bring up calcium and Alk drops.

I have suspected high alkalinity for some time but how do i bring it down?

Water changes with plain seawater. Don't buffer it. Stop dosing your top of wate with alk too, it builds up if you are over doing it.

Well, keep testing your alk daily....you should see it start to drop on its own. no need to do anything quick or drastic here...

I have had luck just lettting it drop naturally....if youre feeling crazy, maybe dose the CA part with out the Alk part for a day or 2 or 3....main thing right now is keep testing daily, montoring the drop....

I say try to get it to @ 9....

be patient you should see positive results at some point.

Why are you trying to raise calcium and magnesium btw? Those numbers are good... Will probably come up a bit as dkh goes down as well.

I am not buffering the top off water: pure RODI water




I have been dosing only Calcium and and adding Mag to help in an effort to naturally bring down Alk. Also, I do 5 gallon water changes every week and that should have an effect but to date it has not.

Again, I am at a loss, because the simple answers I have tried with no luck. What other ways are there to bring down Alk?

Thank you. But "ugh", draining water is the last thing I wanted to hear. I guess Im going to have to BUY a load of water. Thanks, will let you know how this works out.