Unsolved KH issue

[Woof77]

For the past 6 months, I have been struggling with KH dosing. Having to try so many different method and products using recommendation from BRS and forum but none seem to help in stabilizing or most importantly, make sense on the dosing amount that doesn't seem right in my 3 ft tank which only have 4 SPS frag and 3 LPS.

Recently, I switch to Soda Ash bought from BRS and during dosing, I notice as it mix with the tank water, instead of dissolving, it becomes small particle like powder form which my guess is a sign of precipitation. Currently, I set the KH to dose 40ml in 6 interval and CA to dose 12ml in 6 interval in alternate time and my tank reading has been hovering in the following range:

KH: 6.7
CA: 465
MG: 1440

I am clueless how to resolve this. Tried to measure the daily consumption with only 1 dose a day but even if my daily consumption rate of KH is around 1-1.5 dKH, based on the amount I have dose and the interval, I tend to need to dose more which I believe is wrong. I believe my tank parameter is imbalance and have tried to calibrate my dosing pump and even make use of Hanna instrument and APEX Trident to measure the reading but none seem to give me any clue on how to tackle this abnormally.

Seeking help from this forum and thanks in advance.

 

[Saltyreef]

Sounds like its precipitating instantly.

 

[arking_mark]

So it's hard to know what's going on here with the information you provided.

What is the tank size? 40ml of dissolved soda ash could be dosing very little Alk depending on how much you mixed in with how much rodi. So how much soda ash with how much rodi would be helpful.

That being said, very high Ca levels could be limiting your Alk. Our hobby test kits are pretty bad for Ca.

Also, 6.7 Alk is certainly acceptable in our hobby. However, reef chemistry is pretty well understood...so dosing something should have a pretty direct and calcuable impact. If your not getting this, something isn't quite right.

I'd suggest:
1. Get an ICP test or confirm your measurements with other testing (maybe LFS) to get accurate info on your parameters.
2. Stop dosing anything and switch to larger water changes (20% or larger weekly or more frequently) until you figure out what's going on. ASW provides appropriate parameters for your tank.

 

[elysics]

How much flow is there at the point where you dump the sofa ash solution in?

 

[redfishbluefish]

My guess is that your testing is off. With so few frags, and assuming a smallish tank (at three feet long), 6 doses of 40 mls each is a load of alk. Have someone else measure you alk and calc....either a reefer friend using their kits or your LFS.

 

[Woof77]

So it's hard to know what's going on here with the information you provided.

What is the tank size? 40ml of dissolved soda ash could be dosing very little Alk depending on how much you mixed in with how much rodi. So how much soda ash with how much rodi would be helpful.

That being said, very high Ca levels could be limiting your Alk. Our hobby test kits are pretty bad for Ca.

Also, 6.7 Alk is certainly acceptable in our hobby. However, reef chemistry is pretty well understood...so dosing something should have a pretty direct and calcuable impact. If your not getting this, something isn't quite right.

I'd suggest:
1. Get an ICP test or confirm your measurements with other testing (maybe LFS) to get accurate info on your parameters.
2. Stop dosing anything and switch to larger water changes (20% or larger weekly or more frequently) until you figure out what's going on. ASW provides appropriate parameters for your tank.

Sorry for not making this clear. I mix 400g of soda ash with 1 gallon of RODI water as my mix and dose using dosing pump.