Constant drip water change system

[Octavio Salles]

I'm not new to aquariums (although I have been off for over 15 years), but recently I've been seriously thinking about raising wild discus in a black water biotope tank. But by reading the forum I was a bit worried about the need for constant large water changes (daily or every other day). So I thought about an automated system to do that for me. I know some people love to do it and it’s part of the hobby, and in the beginning I think I would to, but after a while I suspect it might get boring/tiring. My profession and number one passion, photography, already consumes a lot of my “enthusiasm”, I really don’t think I will have time for 2 such high demanding activities, lol…

Anyway, I thought out a constant and fully mechanical drip water change system using the tap water and to my surprise I found out that that already exists and a lot of people do it, some very successfully for several years! But before digging into it I checked my city water data for the past 2 years and these are the general results, I think they are honest because the present data matches my test kits (mg/L = ppm):

pH: 6.8 to 7.2
Total Hardness (GH): 38 to 46 mg/L
Carbonate Hardness (KH): always less than 1 mg/L
Ammonia: 0.9 to 1.2 mg/L
Nitrite: always less than 0.005 mg/L
Nitrate: 0.40 to 1.70 mg/L
Chlorine: always less than 0.005 mg/L
Chloramine: 2.5 to 3.1 mg/L

As expected most “organic” results deteriorate during the dry season (winter), when there’s less water in the river where water is captured. Unfortunately they don’t provide water temperature data, but our air temperature here varies from average high of around 30º C (86º F) during summer to 15º C (59º F) during winter, with some extremes high and low. Water temps should vary much less than that and I think the tank heater should cope with it just fine.

pH – is reasonably stable around neutral, actually averaging slightly acid. The tank water may probably be a bit more acid as there will be lots of driftwood in the tank, plus dried leaves and peat in the filter. I don’t care if the water gets stained, I actually want it. I’m not going to have any plants.

GH and KH – very soft water thorough the year, great.

Ammonia – It is very high. How can I cope with it? I thought on having the new water enter the filter first before it goes into the tank, so it has a chance to pass through the bio media first. Second, I may use Prime or Safe every other day to treat the entire tank volume, this way I could get rid of chlorine, ammonia and heavy metals.

Nitrate and nitrite – both are very low.

Chlorine and chloramine – both seem very low to me, but I’m unsure here (help). Should I prime the water every couple days to really get rid of it? I understand chloramine is more toxic, right?

So here is what I sketched, comments below it.


I plan on positioning my tank near a wall where I have water tubing and a faucet on the other side. I can easily have someone break the wall here and bring the plumbing to the tank side of the wall. I live on the first floor of an apartment building, so the water coming down the pipe arrives here with a high pressure. This PVC tubing would lead to the HOB filter. I will need some sort of valve here to finely control the amount of drip. I still need to calculate this, but I think a total of 50% water change every day should suffice, more than it and I think I may have problems with maintaining a constant temperature as well as the effects of prime.

On the glass of the tank itself I can drill an overflow hole and permanently attach a tubing to take the waste water down a drain that exists on the other side of the wall (the other side is a bathroom we don’t use).

While all that may drastically reduce maintenance and still keep good water quality (not to mention no stress to the fish), I will still need to do other things like vacuum the bottom every week, clean the tank walls, rinse the mechanical filters, etc. But of course that’s fine. When travelling I may simply stop feeding my fish for that period, but the constant water change could keep on happening, as long as I trust the system for any leaks or clogs, it should be fine. I must be very careful with the tank overflow intake though, it cannot clog. I may use two separate holes for redundancy, and away from the current.

What are your thoughts? Where your experienced eyes see trouble? :-)

[Northwoods Discus]

There is one problem with percentage water change. Simply dripping in a volume equal to 50% of tank volume does not do a 50% water change. The drips mix with the tank water and then filter out. You would have to run many times the tank volume to get a 50% water change daily. Put some methylene blue in a small container and drip in from a larger container and watch the color change. You may have to drip in 10 times or more the volume of the tank to get 50% change over.
It sounds great but it just does not get the result many people think. You also would have to use way more water to achieve the same result.

[joshvito]

You can calculate the % change, here is one calculator.
http://www.angelfish.net/DripSystemcalc.php

"Chlorine and chloramine – both seem very low to me, but I’m unsure here (help). Should I prime the water every couple days to really get rid of it? I understand chloramine is more toxic, right?"

You will need to remove chlorine and chloramine. Check with your water supplier, and see which they use.
The easiest way is to filter the supply line with carbon. Type of filter will depend on what you are attempting to remove from your water.

My drip system filters through a GE ROSave.Z Depth Sediment Filter and 0.6 Micron MATRIKX CTO Plus Carbon Block.

[Northwoods Discus]

Joshvito that is a nice calculator and simple. I did a 40 gallon tank dripping 40 gallons daily. The first day it was a 63% change, 2 days was 86%, and 99.9% took a week. Assuming no added pollutants which is not happening in a drip system. So to get close to 100% change took 280 gallons of water.

[joshvito]

I have a drip system running on most tanks in my fishroom.
I look at it as an additional water change. I still try to do a manual water change on grow out tanks.

It won't completely remove maintenance, as it doesn't remove "gunk" from the bottom of the tank.

[Octavio Salles]

Thank you very much for the discussion. The issue with the water change percentage makes sense and that is one great calculator!

I plan on a tank of around 65 gallons, so according to the calculator if I drip in 52 gallons of new water every day I will have an 80% water change every two days, or 55% every day - forever, even when I am away. I think this should be enough to maintain toxic wastes in control, especially considering that the nitrate in my tap water is close to zero. Also, please consider that I don't want to breed them, and I will get adult fish only, so I don't think I need absolute zeros in every parameter.

Now regarding chlorine I just did a test on new and aged water. The aged water (24 hrs) showed zero while the new water directly from the faucet barely showed any chlorine, almost zero I would say. But yes, my water company uses chloramine too as indicated in the original post, averaging 2.5 to 3.1 ppm.

My main doubt is how much prime I wil need and if that will be effective in controlling the ammonia, together with the bio filter.

[Skip]

the way i look at it.. you don't DRIP WATER CHANGE your toilet..

you FLUSH it with new water..

but to each there own.. i like to keep it simple.. you know.. the KISS method

[Northwoods Discus]

I use well water so do not have to worry about chlorine. I would think dripping it in all day would not raise the level too high but I don't have the experience with that to give a good answer. Perhaps others with drips on municipal water can give more info.

[GlennR]

Instead of a constant drip, how about a periodic partial flush. Maybe you could use a solenoid valve on a timer to flush, then a float valve to refill from a smaller aging tank if you need to age the water. Maybe if you only flush 25% daily the water "might" not require aging?


Perhaps you could set this up in a separate reservoir (or sump filter) hidden under your show tank.

I am not expert, tossing out my 2 cents...

[Octavio Salles]

I use well water so do not have to worry about chlorine. I would think dripping it in all day would not raise the level too high but I don't have the experience with that to give a good answer. Perhaps others with drips on municipal water can give more info.

Chlorine is not a problem here. The amount of chlorine used in my city is very low (under 0.005 ppm), and the water sits in water tanks on top of the building for a while before coming down, so that helps in evaporating almost all traces of chlorine.

[Octavio Salles]

Instead of a constant drip, how about a periodic partial flush. Maybe you could use a solenoid valve on a timer to flush, then a float valve to refill from a smaller aging tank if you need to age the water. Maybe if you only flush 25% daily the water "might" not require aging?

Thanks, but right now I don't see much need for aging the water really, as long as I add some prime every couple days, but I guess I can only really know the answer when I have the tank working and test the water.

What is the main benefit of aging the water? As far as I know, and please correct me if I'm wrong, is to get rid of chlorine (not chloramine) and to stable the pH. The chlorine is not a problem with my municipal water. The pH does rise a little after aging, but I think this might be compensated by the fact that it will constantly mix with the "old" water in the tank, which I presume might have a lower pH because of all the driftwood, peat, etc. So I guess in the end I will have a neutral to slightly acid water. I don't plan on keeping Heckels that would require a much lower pH, instead I want some Cuipeuas. I hope they will thrive in nearly neutral water.

[GlennR]

In your first post you mentioned that your ammonia level is "very high". I was just thinking aging might be good for removing the ammonia.

Maybe a float valve would still be a good idea, as a safety measure in case your overflow somehow happens to clog .

[strawberryblonde]

I've never tried a drip system, but yanno what, that type of system might be exactly what you need for the weeks that you are travelling!

When you're home you could do standard water changes, feed a bit more and vacuum the tank well. Then switch to the drip system, feed MUCH less and I'm thinking they'd be fine with that.

Oh and definitely install a float valve for "just in case". I had a sump for a year and the first time it overflowed I was wishing I'd installed a float valve.

Can't wait to see your tank and fish when you get it up and running. =)

[Octavio Salles]

In your first post you mentioned that your ammonia level is "very high". I was just thinking aging might be good for removing the ammonia.

Yeah the ammonia varies from 0.9 to 1.2 ppm. I wonder how fast can the filtration system cope with this before it intoxicates my fish. Remember that the new water will first pass through the filter. If needed I could probably set-up a second larger bio filter before it reaches the HOB filter, so the new water will pass twice through a bio filter before hitting the tank.

And as for the float valve, yes this is a wise move, I think I should do it so I can travel with ease of mind.

[Octavio Salles]

When you're home you could do standard water changes, feed a bit more and vacuum the tank well. Then switch to the drip system, feed MUCH less and I'm thinking they'd be fine with that.

Yes, this is my plan... do a heavier cleaning and feeding when I'm home.