Switching from RHF recipe 2 to recipe 1.

[Mohammed]

I always used kalk but after a few mishaps with overdosing and eratic evaporation levels I decided to stop. I let my alk drop naturally over a few weeks and began dosing 2 part, in particular RHF recipe 2 as I had it mixed up already.

After adding a few mini sps colonies my demand shot up from 30ml of each to 55ml. Day before last I had to increase it to 70ml and still noticed a drop so increased it another 30mls today. I will test again tomorrow and either marginally increase or decrease the dose to meet my target of 8.

I had my alk at 7.7 and it dropped to 7.15 hence the bump up to 70ml. Tested today and it was back at 7.3 so bumped up another 30ml for a total of 100ml split over 2 doses. Alk at 7:00 and 9:00 a.m and calcium at 8:00 and 10:00 a.m.

So after stopping kalk my ph took a dive and ranges from 7.6 to 7.9.

Considering changing over to RHF recipe 1 as my ph is on the low side now.

I understand thay recipe 1 is 2 times the concentration so do I just start with 50ml assuming my current dose of recipe 2 is 100ml.

Does baking the Bicarbonate of Soda for an hour drive all the water out. What is the likelihood that the recipe is skewed if i do not drive all the moisture out.?

If i chose to use sodium carbonate what amount will I need to add to substitute the baked bicarbonate of soda as we often see guys dosing unequal parts of each component which i want to steer away from?

 

[bertoni]

If the sodium bicarbonate is not baked for long enough, it probably won't all dissolve in the mixture. If that happens, you could just heat the mixture until it dissolves. That'll be fine, and the end result is the same as baking for longer.

I suspect that starting with ½ the dose when switching to recipe 1 should be about right, although the higher pH can encourage more consumption, and thus require a larger dose. If you are using sodium carbonate, my first guess is that 2 cups should produce 1 gallon of supplement. Bulk supplies might vary a bit in their density, though.

 

[drysea]

Well you should get about 2 cups of carbonate for every 2 1/4 cups of bicarbonate that you bake. You could leave it in a little longer to make sure it have released all the water and CO2, or you could just measure 2 1/4 of bicarbonate to start with, cook it and the then mix it. If you had a little that hadn't converted it wouldn't be a big deal.

 

[Mohammed]

Ok great thanks. If i do get sodium carbonate, will it absorb moisture and CO2 or does remain as carbonate.

 

[bertoni]

It will remain as a carbonate for a long time, especially if kept in a closed container.

 

[Mohammed]

Ok perfect. Any ideas whats the difference between light and dense sodium carbonate and which is the correct one to use.

 

[bertoni]

I am not sure what you mean by "light and dense". If you have a scale, you can start with 594 grams of sodium bicarbonate and bake it to make one gallon of supplement.

 

[Mohammed]

From the net.

"Soda ash*is made in three main grades -*light, medium and*dense. These have the same chemical properties and only differ in physical characteristics, such as bulk density and particle size and shape (which affect flow characteristics and angle of repose)."

This is from a 2 part manufacturer.
Soda Ash - Alkalinity


This product can be used alone to raise Alkalinity or in conjunction with our Calcium Part A solution to maintain levels.*

*

Dissolve 475 grams (roughly 2 cups) of soda ash in 3.5L*(0.93 US gallon)*of pure RO water. This mix will make 1 gallon of ALK Part B. You MUST use an ALK/KH test kit to*determine the amount of Alkalinity your aquarium consumes. We suggest a starting dose of 0.10ml to 0.25ml per gallon of system volume. Test and adjust accordingly."

Based on this is it safe to assume that 475 gr of sodium carbonate either dense or light will be a good starting point.

 

[bertoni]

That weight sounds about right. I'm a little worried about soda ash that isn't based on a food-grade product. Your description sounds like a commercial bulk product. What is its intended application?

 

[Mohammed]

I assume its for glass manufacturing. I will have to source another supplier. I will post the CoA once i have it.

Thanks for all the help this far.

 

[bertoni]

You're welcome! I'll be interested in what you find.

 

[Mohammed]

Hi Jonathan,

Trying not to make drastic changes to my system and of course reduce alk swings, so have to wrap my head around this properly before I attempt this.

"One gallon of saturated limewater is equivalent to about 86 ml of the recipe 1 DIY 2-part." ...........so basically 1 gallon is equal to 172ml of recipe 2 DIY 2 - part.

If I have to revert back to kalk for its ph increasing properties but disassociate it from my evaporation by means of a predefined dosage via a dosing pump over a 24h period i could in theory add a gallon of saturated kalk daily and reduce my 2 part by dosage by 172ml? My evaporation is currently less than a gallon a day so will have to start at a lower volume.

I can possibly start with 1/4 gallon over 24hrs and see how it afects ph. Would you consider an alternative starting point. The reason for not linking it to my ato is due to inconsistent evap rates.

I have a Reef Octopus KR 100 kalk reactor in my storeroom. Would i just add 2 tsp every 4 days if i dosed 1/4 gallon per day via a doser over 24hrs and reduce my 2 part by 43ml a day?

Is necessary to split dosing of kalk separate to 2 part to avoid precipitation?

Just trying to ascertain the best possible way forward. Baking sodium bicarbonate to make carbonate is not an option at present as my flat doesnt have an oven.

 

[bertoni]

Your math is correct, but the higher pH that the Kalk will bring will tend to increase consumption, so you might not get the full reduction.

I agree that linking Kalk to your ATO sounds like a bad idea. I'd drop the 2-part dose and see what happens. Kalk reactors sometimes seem to produce only partially-saturated Kalkwasser. There are a few theories as to why, but I'd add some extra Kalk to provide some margin, especially to handle possible carbon dioxide uptake.

You might need to split the dosing of Kalk vs the dosing of two-part. If the Kalk is dosed into the main tank with a peristaltic pump (or an equivalently slow setup), I suspect that precipitation will be minimal.