Alkalinity Issues in new tank

[Mick126]

So, I’m at a loss as to what I should or should not do at this point to address my Alk issues, which I’m assuming are due to precipitation.

The tank is approx 5 months old, one fish as of today and NO CORAL, I have an approx 2.5cm (1”) sand bed and around 25kg (55lbs) of Dry Marko Base & Foundation Rock along with some extra Bio-Blocks & Spheres in my sump for extra surface area, all in an approx 365lt (94 US Gallon) tank. I’m using Tropic Marin Pro Reef salt.

I was initially trying to get my Alk levels up to around 8dKH prior to these issues as Pro Reef was a little lower than this and up until a couple of weeks ago I was having to dose 50ml of Carbonate Up daily, a product from Coral Essentials here in Australia which is a Sodium Carbonate based solution and was still not able to maintain it at that level.

So, after doing a bit of research through here I came to the conclusion that I was likely precipitating into the sand bed as several areas were beginning to form clumps, still soft enough to break up in tank at this stage. Any way after doing some reading, I decided to change my Alk dosing solution to Randy’s Recipe #2 (Baking Soda) for the time being as my Ph is and was sitting in the 8.25-8.3 range.

So last week I did my weekly tests and had an Alk of 6.9dKH (Hanna Checker) and decided to bump it up to around 7.4dKH using the Reef Chemistry Calculator using Randy’s Recipe #2. Since then I have been dosing the amount of 18ml (based on Randy’s suggested daily doses for Fish-only with Live Rock) but clearly this isn’t enough as the Alk is 6dKH today (a week later) so should I just keep increasing the amount I am dosing until I can keep it at around the 7-7.4dKH and if so aren’t I going to have the same problem as before, an increasing amount precipitating into the sand bed and or dry Marko Rock?

Other parameters as follows

Salinity – 1.025 (Refractometer)

Calcium – 440 ppm (Red Sea Pro)

Magnesium – 1380ppm (Salifert)

Both PO4 (Hanna Checker) and NO3 (Salifert) are zero but that’s another issue that I am in the process of resolving.





Sorry for the long winded question.

 

[code4]

Glad you are addressing the phosphate and nitrate issue also. No expert on the dKH. But seems you have been reading the right information to fix it. You mentioned baking soda. I am assuming you are baking it for the suggested time and are using soda ash?

 

[Randy Holmes-Farley]

I’d keep the alk is the 7dKH range using baking soda and not do things to raise pH. That should limit any precipitation.

 

[Mick126]

Glad you are addressing the phosphate and nitrate issue also. No expert on the dKH. But seems you have been reading the right information to fix it. You mentioned baking soda. I am assuming you are baking it for the suggested time and are using soda ash?

Not baking the Baking Soda as my Ph was already sitting at 8.2 so decided to try Randy's recipe #2 which wouldn't cause further Ph rises.

 

[Mick126]

I’d keep the alk is the 7dKH range using baking soda and not do things to raise pH. That should limit any precipitation.

Thanks Randy.

 

[Mick126]

So after around 2 weeks of dosing baking soda instead of Soda Ash Im still using around 70ml a day to keep Alk at around 7dKh, which to me still seems excessive seeing as I dont have anything other than rock, fish and some snails and I realise that the snails will be consuming some of that but to my way of thinking this is still an excessively large amount to be consumed daily. Am I over-thinking this or should I just keep trucking along with whatever amount I need to keep it at that level.
TIA

 

[code4]

@Randy Holmes-Farley is who suggested you do that. With that said he is the person I would ask. Clarify how long you should keep up that dose.

Good luck

 

[Mick126]

@Randy Holmes-Farley is who suggested you do that. With that said he is the person I would ask. Clarify how long you should keep up that dose.

Good luck

Thanks, am hoping that Randy sees this at some point, I'm probably over thinking it but of all the tanks I've had over the years I've never had this issue, to this extent.

 

[slingfox]

When you test the all of freshly mixed salt water does it read within the range expected?

 

[Mick126]

When you test the all of freshly mixed salt water does it read within the range expected?

Yup testing close to what it should be; am using TM Pro-Reef but I have been bumping up the Alk a bit prior to doing a 10% water change, have been using soda ash for that, not sure, maybe that could be a problem, might just leave the next water change as is next time see if that changes anything.

 

[Randy Holmes-Farley]

So after around 2 weeks of dosing baking soda instead of Soda Ash Im still using around 70ml a day to keep Alk at around 7dKh, which to me still seems excessive seeing as I dont have anything other than rock, fish and some snails and I realise that the snails will be consuming some of that but to my way of thinking this is still an excessively large amount to be consumed daily. Am I over-thinking this or should I just keep trucking along with whatever amount I need to keep it at that level.
TIA

Isn’t that half as much alk as before, since baking soda recipes are half as potent?

In any case, it’s fine to let the alk drop for now.

Do you notice any signs of precipitation?

 

[exnisstech]

Maybe think about switching to a salt that mixes closer to 8 dkH and avoid the hassle of chasing it. I'm not sure if there's something going on with your tank but many people run tanks with coral and maintain alk with just water changes. Obviously those aren't high demand tanks.

 

[Mick126]

Isn’t that half as much alk as before, since baking soda recipes are half as potent?

In any case, it’s fine to let the alk drop for now.

Do you notice any signs of precipitation?

Was actually dosing around 50ml of Soda Ash a day before the switch.

Still a little precipitation going on maybe, cant really tell as the small amount that is going on with clumping in the sand bed is easily broken up when cleaning the bed, the only areas that are a little harder are right up against the rock work. So I would say if its still going on it does not appear to be getting worse. Ph is sitting at 8.2.

As for letting the alk drop, (its sitting at 7dKh at this time) how far can I let it drop as I have the first shipment of Acros coming this week which will be going into this tank after dipping and then sitting in my QT for a couple of weeks.

 

[Mick126]

Maybe think about switching to a salt that mixes closer to 8 dkH and avoid the hassle of chasing it. I'm not sure if there's something going on with your tank but many people run tanks with coral and maintain alk with just water changes. Obviously those aren't high demand tanks.

Had thought about changing, but I think I'd prefer to continue with the TM Pro at this time, I like how easily it mixes and it seems to stay pretty stable after mixing/sitting, also don't see any of the residue in my mixing containers as I did with one of the others I tried before using this. Not really trying to chase the numbers yet but as I plan on an SPS dominant tank I thought I would start getting the numbers up just a little, at this time I'm happy for it to sit in the 8-8.5 range.

 

[Randy Holmes-Farley]

Was actually dosing around 50ml of Soda Ash a day before the switch.

Still a little precipitation going on maybe, cant really tell as the small amount that is going on with clumping in the sand bed is easily broken up when cleaning the bed, the only areas that are a little harder are right up against the rock work. So I would say if its still going on it does not appear to be getting worse. Ph is sitting at 8.2.

As for letting the alk drop, (its sitting at 7dKh at this time) how far can I let it drop as I have the first shipment of Acros coming this week which will be going into this tank after dipping and then sitting in my QT for a couple of weeks.

It is half as much added alk, even with the same dosed volume. That was my point.

With acros coming, I’d maintain 7 dKH with the baking soda and not try to boost alk more or lower organics or phosphate (both of which reduce precipitation).

 

[Mick126]

It is half as much added alk, even with the same dosed volume. That was my point.

With acros coming, I’d maintain 7 dKH with the baking soda and not try to boost alk more or lower organics or phosphate (both of which reduce precipitation).

yeh knew that was what you were saying.
I'm guessing this will eventually settle down?
Both phosphates and nitrates are reading pretty much zero as of last Friday.
Thanks for the advice.

 

[Randy Holmes-Farley]

Feeding more would potentially help both low nutrients and precipitation. :)