do I need to dose?

[thisoldfish]

Hi,

I have a 6 month old 65g/30g sump system. Mixed reef with mostly softies, Pocilopora, Goniopora, Bird's nest, Pavona. I had/have a green hair algae problem (nitrates were 5-10ppm) and I started dosing NoPox on a pump for past few weeks.

My levels have been fairly constant at: pH 8.2, dKh 7, Ca 420, Mag 1275-1300, nitrate 1-2ppm, phos zero.

I dosed with some Mag to bring it up to 1305, haven't messed with it since.

Questions:
1) I'd like my dKh a bit higher- more 8-9 than 7. Do I need to add a dosing pump or is 7 ok? And, if I add alkalinity do I need to also boost my calcium a bit? (and I guess my Mg too)?
2) I'm confused about how to dose the calcium/alk-- when I use the cacium or alk calculators on BRS site I get a finite volume for dosing, IE 126ml of calcium. How does that translate into pump dosing? How long of a period do you spread that 126ml over? Not quite understanding that part- because if that's the amount to bring your calcium to desired level then how do you figure out the basal pump rate for every day?

Thanks in advance!

Brad

 

[Justfebreezeit]

You use that number to hit your set target.

Then let your system run 24 hours and retest. Whatever you lost in that time is what you dose.

You might have to test daily until you can get it dialed in. Cheers

 

[thisoldfish]

oh-- so I add that amount at one time (And theoretically my tank is corrected to goal). and then do nothing for a day and the difference is what I will then dose daily? (understand need for frequent testing)

Thanks so much

 

[Randy Holmes-Farley Verified Community Expert]

7 dKH is fine. So is 8-9 dKH, but I would not assume you need a dosing pump, even if you choose to dose calcium and alkalinity. You likely will not need this much every day. You can boost it, then watch how much it drops in a day and you can see what a daily dose might look like.

 

[Justfebreezeit]

Add alk slowly, drip it in. Calc doesnt matter as much as long as you aren't just dumping buckets of it in.

 

[GoVols]

If you've got an Auto Top Off System you could dose Kalk within your top off water.

 

[redfishbluefish]

Might want to check this out:

How Much Two Part Do I Need


Once you get to the levels you want, you will then need to manually dose....maybe daily, every other day, or whatever the demand of the tank.

 

[thisoldfish]

Thanks all

 

[thisoldfish]

Thanks all. Appreciate the advice. With kalwasser: if I add to my topoff container (I have a 30g trashcan that is topped off by my RODI), does that mean I should turn off my RODI and let the container empty before refilling? Any way to measure the concentration of Kalk in my topoff container as it’s diluted by my RO refill so I can leave my RODI on and just add kalk appropriately? Or is it better to just set up some drip system and know then it’s a constant concentration?

Thanks much.

 

[Randy Holmes-Farley Verified Community Expert]

Thanks all. Appreciate the advice. With kalwasser: if I add to my topoff container (I have a 30g trashcan that is topped off by my RODI), does that mean I should turn off my RODI and let the container empty before refilling? Any way to measure the concentration of Kalk in my topoff container as it’s diluted by my RO refill so I can leave my RODI on and just add kalk appropriately? Or is it better to just set up some drip system and know then it’s a constant concentration?

Thanks much.

What size container is it?

How fast/how much does the ATO add at once?

I mixed up a batch of 130 gallons at a time (3 x 44 gallon brute cans plumbed together) and let it run for a month, then refilled.

 

[thisoldfish]

30g reservoir for my RO ATO water. Not really sure how much it's adding.. I have a float valve so it's always full

 

[Randy Holmes-Farley Verified Community Expert]

30g reservoir for my RO ATO water. Not really sure how much it's adding.. I have a float valve so it's always full

The issues are:

1. A float valve may stick open.
2. If you deliver too much in one shot, the pH may rise excessively, at least locally where you are delivering it.

So even in an ATO, reasonably slow delivery is desirable.

 

[thisoldfish]

ok.. so maybe a gravity slow drip above the sump is best bet for me

 

[Rakie]

ok.. so maybe a gravity slow drip above the sump is best bet for me

Kalkwasser in the ATO is okay, the problem is stability. Some days are hotter than others, maybe you have a fan tick on and your tank evaps more. Then you have an unsteady dose of kalk and you start getting higher numbers, which may be undesirable.

Having a giant 30g trash can with a never ending RODI top off means you're like the one person Kalk in the ATO isn't gonna help

A slow drip will work. Or even an inexpensive single head doser like the BRS one ($50) and dose saturated kalk.

(Saturated Kalk water is just water that has been mixed with Kalk and allowed to settle. Its the top 90% of the water that's clear, and none of the muck on the bottom)

 

[thisoldfish]

Yeah I actually have one of those BRS pumps running NoPox.. but bringing my nitrates and phosphates to zero didn’t erradicate the hair algae so maybe I’ll bag that/accept the nitrates of 10/phosphates 0.1 and use that pump for some kalk instead! Thanks. Appreciate the feedback. This stuff gets complicated when you’re not experienced w dosing

 

[Rakie]

Yeah I actually have one of those BRS pumps running NoPox.. but bringing my nitrates and phosphates to zero didn’t erradicate the hair algae so maybe I’ll bag that/accept the nitrates of 10/phosphates 0.1 and use that pump for some kalk instead! Thanks. Appreciate the feedback. This stuff gets complicated when you’re not experienced w dosing

That would be MUCH more stable for Kalk and solve your problems at the same time. Make sure to dose very small amounts often.

I like to point out Julian Sprung doses alk every 10 minutes -- Stability is king.

 

[thisoldfish]

and- just so I don't zap my tank because I don't understand:

I was reading on another thread that 20ml kalk is needed to boost dkh by 0.1 in 100g saltwater. If I had 100g (which I don't- I have 65g), then I'd need 200ml/day to boost dkh 7 up to 8? My BRS pump only runs at 1.4ml/hr.. so I'd be way below that (running 24h/day it's will pump 33ml). So, should I just mix up kalk, run it in my BRS pump and frequently test the calc/dkh/pH? seems that this pump rate might not be enough?

Feel like I'm missing something..

 

[thisoldfish]

forgive my brain fart.. my BRS pump is 1.4ml/MINUTE not hour!

 

[Randy Holmes-Farley Verified Community Expert]

You can use this calculator to determine the effect of different amounts of limewater:

http://reef.diesyst.com/chemcalc/chem_calc3.html

I think this statement is seriously inaccurate:

"I was reading on another thread that 20ml kalk is needed to boost dkh by 0.1 in 100g saltwater. "

Reality:

20ml kalk in 100g saltwater boosts alkalinity by 0.006 dKH

 

[Randy Holmes-Farley Verified Community Expert]

BRS dosing pumps (1.1 ml per min or so) are not generally optimal for dosing limewater to a decent sized tank since they will be running 24/7 and may not keep up.

If you want to dose a half gallon to replace evaporation in your system, the pump will need to run for 29 hours.