Very Low Kh Suggestions

[s007]

Hi, my smallest 140 liter tank has low KH which i've just noticed, Done test on KH/Alkalinity Salifert and got results: KH value in dKH 5.8/ Alkalinity in meq/L 2.06
Ive done test on PH and it came up 8.0 to 8.5 (not sure as light in room wasn't that good) Please note PH was done with Tropical freshwater PH test as my marine one just finished so im not sure if its correct.

As far as i know 2.06 alkalinity is perfect but KH is way too low and need to bring it up to 7-8 KH, I think this might be due to use of Coraline algae using it up as i can see them growing (some times so much that even cover my green polyp corals.) and i guess i wasn't putting anything back in tank as coraline algae used it up.

Water changes 20-25% pw
Im going tomorrow to get KH+PH buffer but is that the only option and any suggestion on what to look out for next time. Just need some advice from mature marine fish/coral keepers.

Thank you for your time reading this.
Regards,
Sergey

 

[ozzie2011]

Bicarbonate of soda is cheaper and will raise KH, 1 tsp per 20 gallons if I recall

 

[seffieuk]

In a tank of 140 litres imo you shouldn't have to start adding anything!

With regular 25% weekly water changes using a good salt, with high calcium and mag levels you really should not need to add anything.

How about taking your water into your lfs and getting all your stats checked?

Also, do you have a powerhead giving good agitation to the surface of the water?

Seffie x