Spec'ing Kalk topoff dosepump for AP24...need help

[sayn3ver]

Been browsing the APT instruments webpage. Since BRS is out of their line of pumps I am considering just ordering a bare pump from APT. There is a write up on here about these...these are the "drew's doser" pumps. They come in a variety of sizes, speeds, and flowrates.

Anyways, I plan on using the output from my Tunze Osmolator to power this pump. A quick look at the tunze transformer reveals 11v and 1600ma. I spoke with the Tunze rep on reefcentral a few months ago and he said the Osmolator unit itself uses/holds 400ma so the power feeding the stock tunze pump is 11v and 1200ma.

I want to do this because I want to use KALK in my topoff water. However, an ap24 is not exactly a large tank and kalks ph as we all know by now is very high (ph 12 roughly when saturated).

The issue is the Tunze osmolator controller will run only for a max of 10 minutes before it shuts down and then require a manual reset (safety feature).

My tank will be running a 150w metal halide lamp, a vortech pump, probably a mj900 for return pump and more than likely one of those 2x azoo fans when summer htis.

My current 20g high holding tank with only 65w PC lighting eats about 2 quarts in 24 hours. Does anyone have a suggestion for the flowrate I should be getting for my AP24?. I figured the BRS stock 50ml/min would work ok but I never have used the tunze unit before and don't know how sensitive the optical sensor is nor do I know much water per inch the tank holds (more difficult to estimate the volume with the false wall and non-rectangular shape).

More so, what is the safe rate of adding saturated limewater?

Many variables to consider And I have little to no experience with the like.

the ones I were looking at had either 62ml/minute and 38ml/min. However there are many combinations and sizes to create a variety of different flow rates.




EDIT: obviously, an 18x18x18 cube is about 25 gallons. using an online calculator, 1/2" drop in this tank is about 0.7 gallons (0.7*128oz = 89.6oz * 30ml = 2688ml). The 62ml/min will pump about 620ml in 10 minutes.

in 1 hour the 62ml/min pump will move about 124oz of liquid, 4oz shy of a gallon/hour.

The million dollar question is how do I balance the tunze 10minute limit and my tanks evaporation rate while taking into account a safe rate of addition for the limewater? I have only ever manually topped of my tanks up until this point.

 

[cherubfish pair]

You might want to try one of these flow control pinch valves.

 

[sayn3ver]

I would prefer a peristaltic pump for my top off. The tunze rep suggested that i use a micro ball valve with the stock tunze pump.

however.....

1) tunze pump is not rated for kalk water use. It can feed a reactor but not recommended for direct use

2) the tunze pump is much more flow than I need. the micro ball valve is not constant and would need to be dialed in everytime after cleaning th valve. This is something I want to avoid.

3) the tunze pump does not fit in my top off container.

since those valves will not work on a peristaltic pump I am back at the beginning.

 

[cherubfish pair]

If you can't fit a pump in your dosing reservoir, run an aqualifter this way.

drill a 1/2" hole at the bottom of your container and insert a 1/4" uniseal. Put an airline hose through it and attach to an aqualifter with the aqualifter's out put going to the sump.

 

[sayn3ver]

once again,

1) the aqua lifter is rated fro about a years worth of use prior to it taking a dump if using kalk, or so I've been told.

2) I would have to buy the tunze switched outlet for it to be used with the osmolator

3) it is rated at 3.5gph flow rate which when converted is...224ml/minute. I feel this is a bit high of a flow rate for kalk in a 24gallon tank.

according to the reefing articles it seems to be a grey area....

for single dosing....

Delivering a small amount of limewater all at once. Adding 1.25% of the aquarium's volume (1.25 gallons of limewater per 100 gallons of aquarium water) as saturated limewater all at once raises the pH by 0.6 to 0.7 pH units. Such an increase is clearly too large. Adding a smaller portion all at once can, however, be acceptable. Adding, for example, 0.25% of the aquarium volume (0.25 gallons or 1 L of limewater per 100 gallons of aquarium water) will raise the pH by only 0.1 to 0.2 pH units. Unless the pH is high (>8.4) before the addition, that amount is likely acceptable.

if .25% is the case for a single dose...

example, 24g x 128oz/gal = 3072oz
3072oz x 30ml/oz = 92160ml
92160ml x .0025 (.25%) = 230.4 ml

So 230ml is roughly the safe limit of addition at a single shot so if I ran the aqualifter for 1 minute, I would be just shy of the recommended limit. However, what if the sensitivity of the osmolator needs more than a minute worth of topoff?

What I am confused about is whether or not this is in a 24hr period or not.



I feel like float swtiches and a relay topoff system would be so much easier with this thing. The whole 10minute limit of the Tunze unit is really funking things up.

Or am I just way overthinking this?

 

[sayn3ver]

The whole tank is going to be run by an Apex controller.

Would I be better off just buying some cheap float switches and just have it be my ATO? I heard nothing but good things about the tunze unit and bought it a long time ago prior to this tank build. Its never been used which is why I have all these questions. i am thinking about just setting it up in a bucket or the like and see just how sensitive the optical sensor is.

 

[sayn3ver]

I have a feeling this is not meant to be. been doing some more reading and it seems nanos are just not meant to be topped off with kalk.

I could drip kalk or run an extremely slow peristaltic pump to dose it separately but topping off seems to be a dangerous and at odds with each other.

Does anyone have an thoughts on the subject?

Tank is planning to be zoas and LPS. If I end up including SPS or a clam I would go the 2 part route with dose pumps.

I figured though that topping off with a mild kalk (1/2 or 1/4 teaspoonful per gallon) would help me out and be easier than setting up a 2 part system for zoas and softies.

 

[cherubfish pair]

however.....

1) tunze pump is not rated for kalk water use. It can feed a reactor but not recommended for direct use

I don't know if there is an small internal pump for kalkwasser.

1) the aqua lifter is rated fro about a years worth of use prior to it taking a dump if using kalk, or so I've been told.

The aqualifter is built the same way as an air pump. Uses a rubber diaphragm and they can be replaced.

This is all my opinion BTW. If money is not an issue and you're going to be doing a lot of dosing I'd spend $100 on a peristaltic pump.

 

[sayn3ver]

cherub,

me and you must be missing each other in our responses. :lolspin:
I set out looking for a peristaltic dose pump for kalk topoff. The APT industries is the manufacturer of the "drew's doser" pumps available on Bulkreefsupply.

They make several different pumps of various speeds and types. Their 12vDC pumps will work with the tunze osmolator controller...the osmolator's stock tunze pump is connected to the unit via cooper wire with the wire ends held into terminals with screws. This allows one to switch pumps used with the osmolator system with other 12vDC powered pumps granted they fall within spec of the osmolator controller's output (11v and 1200ma).

My concern initially was choosing an appropriate flowrate for the peristaltic pump. They come in various flow rates, everything from .6ml/min to 62ml/min.
After doing research it has occurred to me that topping off with kalk is difficult to do in a nano. More people top off with plain ro/di and either gravity drip or use a slow peristaltic pump with a separate reservoir.

I did not want to use the stock tunze pump to topoff with kalk because it is not supported for that use(can be used to feed a reactor but not for submerged use in kalk solution). Its flowrate is alos to high for safe nano use with kalk topoff.

The same goes for the tom's aqua lifter pump. I find it inadequate for my situation as well.



However, there are those using kalk to topoff with and I am curious how they are doing it safely.

My concern initially was finding a peristaltic pump to use with the tunze Osmolator. Not only does the pump need to be able to top off enough water within the 10 minute windows the tunze unit allows, it must do it slow enough to not cause a drastic ph swing in the tank.

If i choose not to topoff with kalk but to dose it separately I am about as equally perplexed as to what flowrate to get. Do i get the .6ml flowrate and run it 24/7 (0.6ml x 60 minutes x 24 hours = 864ml/day. My current tank without MH lighting evaps about 2000ml a day.)

If I end up with SPS and a coral load that maxes out this "drip" and I want to have all my topoff as kalk i would need a faster pump.


They have one that flows 38ml/minute. This one may work in both circumstances, it might be enough for topoff use or i can run it for a minute several times a day as a separate kalk doser.


I just don't know what to do at this point.

 

[cherubfish pair]

Do you have a controller with a switch apart from your Osmolator?

 

[sayn3ver]

Well I will be running an apex unit for most of the other functions.
As for the switch, i can add float switches to the apex unit.