# Anyone dose throught their top-up?



## nphsmith (28 Oct 2013)

I will be using an RO-based auto topup. While I won't be able to have terribly exact basis for how much is topped up in a week, I'm hoping that it will be good enough for me to dose EI. My thinking is that
a) Less work for me
b) No missing of doses
c) Slow steady input of elements rather than huge amount once/day/week.

But...I don't see many people doing this. Am I missing something obvious?


----------



## Nathaniel Whiteside (28 Oct 2013)

You could use a peristaltic pump for fertilisers? As some do on here. You look to know your reef scene well, so you'll be a whizz


----------



## nphsmith (28 Oct 2013)

Nathaniel Whiteside said:


> You could use a peristaltic pump for fertilisers? As some do on here. You look to know your reef scene well, so you'll be a whizz


 

I could - but i will be 'dosing' RO anyway, so figured it would be easy to add it in that way.


----------



## Nathaniel Whiteside (28 Oct 2013)

Apparently, something happens to the Iron in the Micro mix when in the same solution as the macro.
I think it makes iron unavailable to the plants for uptake. So, going on that, your plants will have an Iron shortage.

I'm no professor, but one of the 'Pros' will be able to tell you exactly whats-what.


----------



## Nathaniel Whiteside (28 Oct 2013)

But you could put your macro mix into the Top up water and dose the micros via peristaltic or manually by powder or solution..?


----------



## three-fingers (28 Oct 2013)

I would have thought that the nutrients would degrade in the top up tank, unless you add a lot of preservative (not sure if that much would be considered safe) or were topping the RO tank up with nutrients daily (defeats the purpose).

Peristaltic pumps are a great option though, as mentioned above .


----------



## nphsmith (28 Oct 2013)

Nathaniel Whiteside said:


> Apparently, something happens to the Iron in the Micro mix when in the same solution as the macro.
> I think it makes iron unavailable to the plants for uptake. So, going on that, your plants will have an Iron shortage.
> 
> I'm no professor, but one of the 'Pros' will be able to tell you exactly whats-what.


 
That sort of makes sense - hence why there are 2 solutions, presumably.




Nathaniel Whiteside said:


> But you could put your macro mix into the Top up water and dose the micros via peristaltic or manually by powder or solution..?


 
Macro is daily and micro weekly? That would be fine.



three-fingers said:


> I would have thought that the nutrients would degrade in the top up tank, unless you add a lot of preservative (not sure if that much would be considered safe) or were topping the RO tank up with nutrients daily (defeats the purpose).
> 
> Peristaltic pumps are a great option though, as mentioned above .


 


But...if they don't degrade in a 'peristaltic container', why would they degrade in an 'autotopup container'?


----------



## Nathaniel Whiteside (28 Oct 2013)

Macros is daily yes and Micros normally every 2-3 days. so you could do Micros twice weekly?


----------



## Andy Thurston (28 Oct 2013)

I think i read about George farmer dosing macros and micros together daily, in one of his journals, without any problem. I think the iron reacting is more of a problem when stored in the same bottle.
Do the waterchange and topup daily and ad nutrients daily with dosing pumps.

And just to throw a spanner in the works i use tnc complete which contains macro and micro so hows that work then?
 I have read about micro mixes going off in storage bottles and people adding preservatives


----------



## Nathaniel Whiteside (28 Oct 2013)

Big clown said:


> I think i read about George farmer dosing macros and micros together daily, in one of his journals, without any problem. I think the iron reacting is more of a problem when stored in the same bottle.
> Do the waterchange and topup daily and ad nutrients daily with dosing pumps.
> 
> And just to throw a spanner in the works i use tnc complete which contains macro and micro so hows that work then?
> I have read about micro mixes going off in storage bottles and people adding preservatives



Yeah you can get preservatives to preserve in bottle. Don't know how they would work out watered down in a top up container.


----------



## Nathaniel Whiteside (28 Oct 2013)

And it's called absorbic acid BTW.


----------



## Andy Thurston (28 Oct 2013)

Thats the one I've read that many chemical names to do with fishtanks its hard to remember which one does what. I think there is another that can be used too.


----------



## three-fingers (28 Oct 2013)

> But...if they don't degrade in a 'peristaltic container', why would they degrade in an 'autotopup container'?


Because the 'peristaltic container' would be much smaller (peristaltic pumps are specifically used to dose small volumes at a time) and contain a far more concentrated solution of the salts, killing any microbes that may change the properties of the nutrients. The biofilm on the inside of the RO container for starters.

Even in concentrated homemade fertilisers a preservative is often used to prevent this, potassium sorbate. Not really a good option for an RO tank IMO.


----------



## nphsmith (28 Oct 2013)

three-fingers said:


> Because the 'peristaltic container' would be much smaller (peristaltic pumps are specifically used to dose small volumes at a time) and contain a far more concentrated solution of the salts, killing any microbes that may change the properties of the nutrients. The biofilm on the inside of the RO container for starters.
> 
> Even in concentrated homemade fertilisers a preservative is often used to prevent this, potassium sorbate. Not really a good option for an RO tank IMO.


 

Thanks, that makes sense.


----------



## Nutty (28 Oct 2013)

Slightly aside here so apologies 





Nathaniel Whiteside said:


> absorbic acid


 or Vitamin C to most is used as a pH regulator, Antioxidant, Flavour enhancer ect... but even by APFUKs site and quiet a bit of literature its highly unstable in the presence of metal ions... and where does it go? with a load of metal ions! I've also seen great instability when just added to water and stored at medium temperatures, but please correct me if i'm wrong i'm just really not sure why it is recommended :S


----------



## ceg4048 (29 Oct 2013)

Vitamin C is an acid. The chelates in the micro mix work best at low pH. In the bottle, therefore it keeps the Iron from reacting with the PO4. That's all.

Potassium Sorbate is a mold inhibitor. It works fine and there is no need to worry about these additives.

Cheers,


----------



## Nathaniel Whiteside (29 Oct 2013)

ceg4048 said:


> Vitamin C is an acid. The chelates in the micro mix work best at low pH. In the bottle, therefore it keeps the Iron from reacting with the PO4. That's all.
> 
> Potassium Sorbate is a mold inhibitor. It works fine and there is no need to worry about these additives.
> 
> Cheers,




So Clive, 
Would you advise for or against having a pre dosed with both macro and micro RO top up system?

Would the mix be okay? Or would macro only be better with a manual dosing of micro?


----------



## ceg4048 (29 Oct 2013)

Well it's really up to the individual. If you use JamesC's all-in-one mix then it's fine to dose it concurrently with top up, but if it's actually placed in the top up reservoir and if the volume of the top up reservoir is too large without accounting for the necessary amounts of Vitamin C for that volume, then the pH may not be low enough and the Fe/PO4 issue might be a problem. It will be easy to tell because if it occurs then there will be an Iron Phosphate or some other metal-phosphate  precipitate forming at the bottom of the reservoir.

Cheers,


----------



## Nathaniel Whiteside (29 Oct 2013)

ceg4048 said:


> Well it's really up to the individual. If you use JamesC's all-in-one mix then it's fine to dose it concurrently with top up, but if it's actually placed in the top up reservoir and if the volume of the top up reservoir is too large without accounting for the necessary amounts of Vitamin C for that volume, then the pH may not be low enough and the Fe/PO4 issue might be a problem. It will be easy to tell because if it occurs then there will be an Iron Phosphate or some other metal-phosphate  precipitate forming at the bottom of the reservoir.
> 
> Cheers,



Great. I would imagine that will help the OP no end. As well as re-highlight which chemicals it was, I forgot 


Thanks very much,
N


----------



## nphsmith (29 Oct 2013)

ceg4048 said:


> Well it's really up to the individual. If you use JamesC's all-in-one mix then it's fine to dose it concurrently with top up, but if it's actually placed in the top up reservoir and if the volume of the top up reservoir is too large without accounting for the necessary amounts of Vitamin C for that volume, then the pH may not be low enough and the Fe/PO4 issue might be a problem. It will be easy to tell because if it occurs then there will be an Iron Phosphate or some other metal-phosphate precipitate forming at the bottom of the reservoir.
> 
> Cheers,


 
Rather than worry, I think I'm inclined to put NPK in the RO, and CSM+B manually dose twice a week. That's safe, right?  Then, depending how lazy I am, I can set up a peri pump to do the CSM+B at a later point.


----------



## ceg4048 (29 Oct 2013)

Seems a reasonable approach to me.

Cheers,


----------



## Ady34 (29 Oct 2013)

Are you using the auto top up to actually top up or are you putting it onto an on/off timer to pump an amount of ferts in?
I only ask as if using as a top up your rates of evaporation could greatly vary and this will effect dosing. You'd really need a fairly constant measureable rate of top up to know you were adding enough ferts. You'd be better off with a designated dosing system or just sticking with manual introduction IMO. Dosing ferts doesn't have to be a precise art but you do need to ensure your adding enough regularly.


----------



## nphsmith (29 Oct 2013)

Ady34 said:


> Are you using the auto top up to actually top up or are you putting it onto an on/off timer to pump an amount of ferts in?
> I only ask as if using as a top up your rates of evaporation could greatly vary and this will effect dosing. You'd really need a fairly constant measureable rate of top up to know you were adding enough ferts. You'd be better off with a designated dosing system or just sticking with manual introduction IMO. Dosing ferts doesn't have to be a precise art but you do need to ensure your adding enough regularly.


 

Good point - I will start manually (IF nothing else, to learn what I am doing), and see how much RO the topup is putting in each week, and how consistent it is. I am in London, so my water will be 'pre-loaded' with a fair amount of nutrients, and I will also be using TMC soil, so will have a certain amount of 'buffer' if I underdose. From what I read, overdosing is next to impossible?


----------

