EI dosing w/constant freshwater feed

You want to dose into this feed system or directly into the tank sat daily or 2-3x a week??

It depends on the rate of exchange. If you change 50 Gal in 1 hour vs 50 Gal in 12 hours etc.

I just hard plumb things so I can drain whatever % I want with a valve to drain and another to refill fast.
That allows me all the control and does not take much effort.



Regards,
Tom Barr

 

You are not going to get any significant difference there vs say a daily rapid flush of 10%, 20% etc, or even 2-3x a week water changes, I'd say you'd get better results using 30-50% 2-3x a week for WC's.

At those dilution rates, you really have super clean water even if you feed heavy.
One friend does a daily but slow using about 1-2hour times, so changes about 10-15% but a total of about 30%(about 50% was new water).

Anytime you do slow removal, you also remove a fraction of that new water, this is a highly wasteful process, like RO filters.

While easier for some folks, a simple Solenoid with a pre set drain level, and a float switch(or a dual set just in case) can work well.

I prefer to watch and be there, and I can drain much more water at once and direct where that waste water goes. So 50% is easy and I can do it while I eat, clean the tank, prune, type on the computer etc.

Turn one valve, drains, turn another, fills.
No labor.

I dose after each water change, maybe 1 in between if I did 2x a week.
If you did say 30% 3x a week, simple dose after each water change.

Very easy routine.

While it might APPEAR that the slow drip exchange is groovy, natural etc, and it is, we have that type of set up outside at the lab, in an aquarium, it's less practical. You really do not exchange 100% of the old water, but rather, the same dilution infinite series that you do with the EI.

Say you drip in 10 Gallon per day to a 20 Gallon tank slowly. Only about(I'm not being entirely accurate here) 25% of the water is actually changed, the rest is a partial water change of the new 50% water you are adding, since it's assumed to be mixed.

Maybe that trade off is okay.
I do not know.

I'd personally increase the rate of drain and refill so there is much less remixing and waste, this will make the WC system much more effective and efficient since as you state: the goal is to reduce and remove toxicants(most O2 reducing waste and NH4 production).

I'd focus on more creative ideas there if possible.
Make the water change easier. If you are using RO and want to use that low few gallons flow rate, then the waste factor is roughly 90%, so hard plumb that to add water to the landscape. You can also perhaps store the RO water and flush(instead of waste say 50% of every bit you add to the tank) & refill.

So you waste the RO in that case(and 90% is waste on top of that) at a rather high rate as well.

It might be simpler to plumb the slow drip, but I'd do the hard plumbed valve method personally, over time you will like it. I've done several methods here and it's the most practical and the safest of the 3-4 ways to do it.

Still, if you go to the trouble of installing an automated water change system, might as well do it right and get the best % use out of the water exchanged.

Do it right the 1st time.
Same with CO2, light, scaping, sediment, fish choices, you know the routine and schpiel

Regards,
Tom Barr

 

Yes, the booster pump will increase efficacy so you have less RO waste water. Good point there. Trade off: more energy for the booster pump/cost/electric.

Water pressure is free, the water itself is not(or sometimes is for the most part).

Regards,
Tom Barr