Which is better to match when water changing, alk or salinity?

[brad65ford]

OK so I've learned something simple (yes I know I'm late to the parts), if you want lower alk you can lower the salinity for a WC's,,, simple right? Well if this is true then what is more important or damaging to sps's alk or salinity fluctuation? Reason i ask is would it be better to lower the salinity (with in reason) to match the alk in the tank?

 

[swk]

I would match salinity, especially if you're doing a 25% or larger water change.

I would also try to match alk as closely as possible as well. Again, the more water you change, the more important this becomes.

I would find a salt mix that has an alk reading close to what you keep your tank at.

 

[Reefvet]

You want both the match if you're trying to keep a stable tank for SPS. Slightly higher on Alk with the freshly made water is usual.The amount depends on the brand of salt you're using.

Forget whatever it is you think you learned about lowering salinity to match Alk. That's a slippery slope you'll never get right.

 

[trueblackpercula]

Alk is more important in my book and salinity is more forgiving when to high or to low. I would try when doing water changes to use a salt brand that will give you the desired levels you are looking for. Remember alk swings burn corals fast salinty won't.

 

[brad65ford]

Alk is more important in my book and salinity is more forgiving when to high or to low. I would try when doing water changes to use a salt brand that will give you the desired levels you are looking for. Remember alk swings burn corals fast salinty won't.

Agree, so does anybody know if it per say bad to run an sps tank at 1.22 or something similar. If I were to run IO or RC (which everyone knows runs very high alk) an slowly lower the salinity to bring down the alk to a reasonable level how would the lower salinity effect things?

 

[Dartolution]

I would avoid a salinity that low for a SPS reef. Aim for 1.024-1.026

Im assuming you meant 1.022 not 1.22 as the later is EXTREMELY SALTY.

I use Reef Crystals myself with no problems but this is my experience alone.

 

[Wazzel]

I think it would be better to match the salinity. Alk can be made up for via dosing.

 

[tmb22]

Agree, so does anybody know if it per say bad to run an sps tank at 1.22 or something similar. If I were to run IO or RC (which everyone knows runs very high alk) an slowly lower the salinity to bring down the alk to a reasonable level how would the lower salinity effect things?

1.022 would be too low to run at constantly. Also, matching the alkalinity in your water change water could pose problems with your salinity long-term. If a salt brand has a standard alk of 12 at a specific gravity of 1.026, then matching your alk to 8 could bring down salinity significantly to something like 1.015. Matching your water change water's alk to that of your tanks will slowly drop your salinity to very low levels. I would advise to just match the salinity. If you're doing 15% or so water changes, the alkalinity swing won't be big enough to affect the corals in any significant way.

 

[MBMAX]

match your salinity. even at 10-15% weekly water changes the increase in alk is not that much but if you lower your salinity to match alk you will over time you l harm your corals .

 

[brad65ford]

Thanks guys, i ended up picking up some RS salt blue bucket which is not the pro and much lower alk. Would love to us IO/RC but the ALK is just to high (12.6dhk). Tried experimenting with muriatic acid some time back which did work lowering the alk ;-)

 

[Jettareefer]

IMO coralife salt is the best if your wanting to match both your alk and salinity @1.026 my alk is 9 dkh it also doesn't have the brown residue or white specs like RC/IO.

I just wanted to add I have used RC, IO, Esv, kent, and ect. I prefer the cheap coralife over all of them!

 

[swk]

Thanks guys, i ended up picking up some RS salt blue bucket which is not the pro and much lower alk. Would love to us IO/RC but the ALK is just to high (12.6dhk). Tried experimenting with muriatic acid some time back which did work lowering the alk ;-)

That's what I use as well. Blue bucked Red Sea. My tank has responded very well to it

 

[PaleHorse]

I think it would be better to match the salinity. Alk can be made up for via dosing.

+1 Always match salinity first.

 

[animalkingdom]

In reasonable size water changes the alkalinity change will be minimal from high mix up water. Coral will take up any excess before it becomes a problem in a helathy tank. The additive effects on salinity from water change to water change will definitely not be good though. Match the salinity and forget about alk. If doing greater than 25% changes I would be a little more cautious of the alk though. Still I would match the salinity but I may make sure to use a salt that more closely matches my tank water. For large water changes I prefer IO (lower alk), for normal water changes IO or RC or other brands of salt are fine.