Help with dynamic dosing

[K519]

Hi ive had a simple doser setup dosing all for reef but id like to switch to kalkwasser. im trying to setup a dynamic dosing regimen for kalkwasser using my ph probe. It wont allow to me select my doser because “doser 1 runtime to low” but i believe runtime is 12hrs so i dont understand. Doser is 43ml per minute so it would need to run for 11.5 min every 15min for 12 hours.
Ive contacted support and they keep telling me my doser is 21ml per minute when its clearly stated on their own website that its 43ml per minute and ive calibrated to make sure its 43 ml per minute and have done manual doses to make sure its accurate.
I may be doing something else wrong but its definetly not because my doser is 21ml/min. They replied twice saying the same thing and i feel like they dont even read the email. i do appreciate that its sunday and they are still responding but its not helpful.

Input - ph probe
low point - 8.1
high point - 8.4.
Low point dose - 500ml
High point dose - 50ml (pic says 10ml but i changed that to 50 and saved changes)
If stale dose - 0 ml (is this correct ?I figure if i dont know what ph is i dont want kalk dosed. Also what would cause inactive or stale input ?).
Dose count - 48 (12 hrs dose every 15min if ph below 8.4)
Doser count - 1
Doser 1 — here i try to select my doser but i get red bar on the bottom saying doser 1 runtime too low
Run time 2100hrs and 0900 hrs so 9pm to 9am
Active only in normal

Thanks for your time. Hoping someone here has some thoughts

 

[Carlos]

The problem here is the Stale Dose = 0.

One of the features of DYNAMIC Dosing is to allow you to increase or decrease levels AND maintain them. For example, let's take Alkalinity. You figure out that your tank consumes 100ml to keep the alkalinity at 8dKH. 100ml does not increase or decrease the Alkalinity. But instead, it keeps it steady. This is the amount you should be using for your "Input High" setting. If your alkalinity climbs up to 8.5 and you go back to adding only 100ml, it will not continue to rise. Instead, it will drop until it reaches 8dKH and then level out. You are only adding enough to "maintain" a level of 8dKH.

Stale Dosing was added as an option if your Alkalinity machine (or input reading) stops working and no longer sends information to the HYDROS. For example, the last reading was taken 12 hours ago, which might be too old and is no longer relevant. At this point, what do you do? Do you tell the HYDROS to stop entirely and add nothing? If you do not add anything, the Alkalinity will drop quickly (even below 8dKH).

It would be best to have the HYDROS add something like 75 ml. Assuming that the Alkalinity reading is high, it would allow the level to drop back to normal, but if the level is already 8, it won't allow the reading to drop too much below what you want. It slows down the drop and buys you time to fix the problem without having the alkalinity drop too much.

So when you set the "Stale" reading to something like 0, you negate the option's purpose and forfeit your redundancy/backup option of what happens if the HYDROS cannot get the reading now.

Now the question is, how low can "Stale Dosing" be? It all depends on two factors: the speed of the pump and the run count. The HYDROS will not allow you to run the pump for less than 2 seconds.

If you have a pump rated for 43ml, then 2 seconds is the same as 1.4ml. If your Dose Count was 1, you could set your lowest dose to 1.4, but since your dose count is set to 48, it means each of the 48 times, the pump cannot run for less than 2 seconds or 1.4ml. So your TOTAL lowest dose is 48x1.4=67.2ml

If your pump is rated for 21ml, 2 seconds is the same as 0.7ml. If your Dose Count was 1, you could set your lowest dose to 0.7ml, but since your dose count is set to 48, it means each of the 48 times, the pump cannot run for less than 2 seconds or 0.7ml. So your TOTAL lowest dose is 48x0.7=33.6

I hope this makes some sense to you.