Constant Drip - A different way

[Just Toby]

I thought I would let you guys know what I have been up to.

My ongoing battle to get Nitrates to a stable less than 20ppm has seen me use a Vodka dosed Deltec Nitrate reactor combined with an ion exchange resin and auto water changes og 30-50 gals twice per week (tap water reads as 0 ppm nitrate on any test kit)

I also do 30-50% water changes every weekend without fail.

All of this has given constantly low nitrates but has been a fairly intensive regime.

I have now gone over to a constant drip using an HMA (Heavy Metal Axe - form Devotedly Discus) these remove heavy metals but also Chlorine and Chloramine. I have the tank plumbed for Waste and for Fresh Water. The sump is close to the top and overflows to waste.

I did not want to run 100's of gallons per day due to the cold water and wastage. And I want the sump to do all of the bio removal work so it can work without the constant flow.

I have added a Capillary restrictor which drops the flow to 6 gallons (UK) per hour and I have a timer so it only runs for 3 hours per day (to try it)

As a safety measure I have set my aquatronica computer up with an XY program so that if the level in the sump exceeds the overflow it turns off a solenoid valve to stop the fresh water. I did this as my waste froze over winter and this would have flooded the system. The valve is "normally closed" and if we have a power cut the constant drip will not run to save chilling the tank.

I will let you know how I get on. I stopped the nitrate removal sources that I was using and let the Nitrate go up to 50ppm and I will test daily to see when / if it drops.


Thanks to T1 for his advice on this and the aquatronica as he runs a constant flow.

 

[T1KARMANN]

Wow you are looking for real low nitrates

On my old tank 350 gal I was lucky to get my nitrate lower than 80 ppm and that was with 2 x 25% water changes per week and a shuran nitrate reactor which I tryed running both ways sulphur beads and alcohol

To tell the truth I don't think the nitrate reactors work that well

Rays don't need nitrates that low as my rays were breeding in 100 ppm

It would be nice to get the nitrates as low as you want but I think you will be fighting a battle you can't win unless you go RO

 

[wing888]

You are so lucky to have 0 nitrates out of tap, mine vary around 40-50 out of tap and I mix 30% RO to reduce hardness as well as nitrates which still leaves me with 30-40 on nitrates. My battle with nitrates is consist of constant daily 5% drip and 3x 30% weekly changes so I would be interested with this thread to see how you get on.

 

[Just Toby]

I know I am lucky with the Nitrate at 0 out the tap, I test with 2 different kits every few months on the tap and over 8 yrs of being here I have not seen a colour at all.

I agree about the Nitrate Reactors, mine used to spit out 0 Nitrate water which was great, the next day it might block up and produce sulphide and then I had to increase flow, the bacteria would crach and Nitrite was produced.

My regime never let the levels get above 50ppm but it was hard work and the weekly recharge of the ion exchange was a PITA. and they were never designed for running ON the tanks but they were for tap water.

I hope the daily flow will help and I can find an equilibrium to help reduce the Nitrate, I know they will live in 100ppm (and breed) but I think it is not perfect and when coupled with other water quality issues they can die faster as they are weaker. We know that Rays will stop feeding and show fit like behaviour in very elevated levels so any level must has some negative impact.

Cichlids rub their Gills on the sand at 100ppm so it must irritate and I think it has the same effect as Nitrite reducing the ability to absorb oxygen in the blood. I also have seen colours and activity increase with lower Nitrate and fish in general do seem to show breeding activity when lowered.

This bit might be a bit "hippy" but Nature made plants absorb Nitrate from the water, this is probably plants absorbing an energy source but I also wonder if they are needed in the whole eco system as Nature needs to get rid of nitrate too for life to survive???

I am waiting for my POTHOS to send out some roots and will hope that this has a benefit too.

I am not keen on RO due to the waste and I cannot see that it will help me as the RO water would just be 0 Nitrate too, the same as my tap water...I have got a swimming pool so I am on a water meter and using RO would really up the cost due to the waste element...unless the waste could go in to my irrigation system for the garden....

 

[wing888]

I have been thinking about pathos as well as I am on a meter too!
What I have is I run 3 150 GPD RO membranes in series on the waste of my merlin RO so th waste is minimal and the waste water drips into my garden pond which I'm sure my goldfish appreciate. The merlin RO with the additional membranes on the waste can produce 500-700 gallons in 24 hrs depending on mains pressure and it produces my desired water of 280 in my tds meter which works out to be equivalent to 70/30 mix, I them have another RO system with 3 membranes in series for my daily 5% drip.

Has been like this for the past 2 yrs with good results.

 

[Just Toby]

I have been thinking about pathos as well as I am on a meter too!
What I have is I run 3 150 GPD RO membranes in series on the waste of my merlin RO so th waste is minimal and the waste water drips into my garden pond which I'm sure my goldfish appreciate. The merlin RO with the additional membranes on the waste can produce 500-700 gallons in 24 hrs depending on mains pressure and it produces my desired water of 280 in my tds meter which works out to be equivalent to 70/30 mix, I them have another RO system with 3 membranes in series for my daily 5% drip.

Has been like this for the past 2 yrs with good results.

That seems like a good way to do it, I didnt think the waste pressure would be high enough to run the second RO...RO companies should follow your route!

 

[jcardona1]

I say the lower the nitrates the better. Who knows what kind of long term affects in can have on fish. For example, my old 400g cichla tank had high nitrates all the time. Even after doing weekly 75% water changes, nitrates were still over 80ppm. That was unacceptable for me.

So I finally installed a 24/7 drip system. By dripping 96g a day, I was able to reduce my nitrates to a consistent 10-15ppm (tap is about 5ppm). Not rays, but the same still applies:

 

[wing888]

That seems like a good way to do it, I didnt think the waste pressure would be high enough to run the second RO...RO companies should follow your route!

The pressure will remain constant on the output and waste,its the flow that changes, I have found 3 to 4 membrane in series is about the max any more and its redundant. running RO membranes this way is not ideal if u want pure water but for my needs(reduce hardness and ph ) it is an ideal way for my needs. on the 3rd membrane the output is mote of a drip and the rejection rate is not too good but as mentioned it is ideal for my needs.

 

[Just Toby]

Hey Jose, that cichla tanks is one of the nicest tanks I have ever seen...lovely fish!

Also totally agree on the Nitrate levels.

I am glad to say that over this week the nitrate has stayed at around 25ppm which is down from around 40-50 and that was before my large weekend water change. I will keep monitoring it before every large manual weekly water change as this will be it's worst point it should get to.

 

[PeteLockwood]

Have you ever seen the surge devices people use on saltwater tanks? I think if I was ever gonna set up a constant change system (unlikely I must admit) I'd use one of those to get the new water into the system in one load. It would let you heat the water (i.e. put a heater in the surge bucket) and presumably if located and directed appropriately into the main tank also ensure that the old water is what overflows out of the system. You could probably also use an IV bag to dose the correct amount of dechlor.

This is the kinda thing I'm thinking of.. http://www.breedersregistry.org/Reprints/MFM/v11_aug96/simple_surge.htm