Diy... No More Water Changes!

[And_Hef]

Here's the idea...

My idea would be base off a RO filtering system, sort of.

The cheapest RO system I've found on the net is $150 with 5 stage filtering (@ Lowe's Home Improvement). After reading the purpose of each step, I think, for a planted tank at least, you really only need 2 filters and no RO element. One for large sediments and one for the chlorine (maybe even have 2 for chlorine just to be sure, it's only $25 extra). This would leave the trace element in the water for the plants/fish.

You would do away with the sump all together and have the outlet after the filters dumping into a small container filled with bio balls above the tank (say mounted in the hood/canopy), then draining directly into the tank. That way your still getting good bacteria (since you are not doing a complete RO on the water, the city water should still have nitrates for the bacteria). Then you would just have a gravity drain to a sink or out a window.

Simply put a ball valve before the filters to control how much water is coming in and out of the tank. If the water is cut off, the gravity drain will stop. I would still have a filter or two in place (running all the time, but set at it's lowest/slowest setting) for a backup, which would also keep good bacteria in place.

This would cost about $50-$75 to build and your fish and plants would have fresh clean water all the time. And the big advantage NO MORE WATER CHANGES (still have to do vacuums often).

What does everyone think, will it work?
__________________
Thanks,

AndrewH

 

[dylema]

Are you suggesting that you would have a constant flow of new water comming in and a constant flow of old water being thrown out (down the sink or out the window)?.

Do you have plenty of water where you're from? In Australia we have permanant water restrictions in a lot of places so this idea would not work for us.

I am also confused about still having other filtration if there is a constant turn over of water. Do you propose perhaps to have a tiny trickle of new water in and old out? That idea I like more and then there would be a role for the other filters.

If the city water does have nitrAtes this is not good and the kind of bacteria that consume nitrAtes are anaerobic and produce unwanted waste products along with harmless nitrogen gas. We want the bacteria that converts ammonia to nitrIte (Nitrosomonas sp.) and then nitrIte to nitrAte (Nitrobacter sp.) then nitrAte is removed by water changes (enter your idea).

Also I think most of us fresh water people don't have sumps unless we have serious setups like huge tanks or many smaller ones.

What does everyone think, will it work?

I don't see why not except for the water usage issue.

Dylan

 

[And_Hef]

Sorry I meant nitrItes not nitrAtes. I get those two words mixed up all the time.

Yes, you would have a constant flow of fresh water in and old water out. No water restrictions in the US (except for outside the house lawn watering, etc.). My current water bill is $40 ($10 water, $15 Sewer and $15 garbage pick up). 1000 US gallons of water are $4. The in to tank flow would be somewhere in the 2 to 3 gallons per hours range (or $8-$10 per month), and it might be able to be set lower than that. I think $8-$10 is very little to pay so that my fish have a constant supply of fresh water. Also, the house we just bought has a water well, so supply is not an issue there.

The electric filter would be in place as a backup incase the water flow was stopped for whatever reason, and to help get the extra fish food, fish poo, etc. cleaned up and to host extra bacteria. Not necessary at all, but I will probably have one in place for a little while. I guess you could have one in place and not plugged in and let the fresh water inlet dump into the media of the power filter thus maybe keeping some extra bacteria growing, and if you have a water outage simply plug the filter in.

I currently have a 55 gallon FW up and running and have an empty 90 gallon sitting in my garage waiting for us to move before setting it up. I was planning on building a sump so to connect both tanks together as one larger system. I know you run the risk of spreading illnesses between the tanks, but you also increase the water system from 55 or 90 gallons to 55+90+30 (sump capacity) which is more stable. But with the fresh water always coming in setup I don't think I'll build a sump. (Sumps are also a nice way to get all of the equipment out of the tank. heater, filter, thermo, etc. you'd just have an inlet and an outlet) You really don't have to have a big sump for it to work (I've seen 4-5 gallon sumps that worked great), but the more water in the system the more stable the system.

I think it will work as long as the filter elements do what they say they will do.

 

[Wonderboy]

Not trying to be pessimistic, but I'm not sure of that would be incredibly functional as a fish habitat. Believe it or not, you need all that extra stuff in your old water (to an extent). I think this is a good idea for perhaps a very, very large tank (even still - maybe). I have a 180 US gallon, and I don;t think I would consider rigging a constant exgange up. Again, not a bad idea, but perhaps not so practical.

~ Wonderboy

ps - **just an opinion**

 

[dylema]

Hello again,

I am thinking this through in my head. Even at 2g/h you would replace all the tank water in a 55 in just over a day which is much more than anyone would ever do in normal water changes. Even at 1/3 of a gallon it would turn the whole tank over in a week. If you could get it so it litterally just drips in that might be better.

A quick little experiment I just did, counted how many drips in 5ml = 87 therefore one drip = 0.06ml (approximately) (dip sizes may change) so at 1/3 g/h = 1300ml/h = 22000 drips/hour =360ish drips/minute ok so thats really a trickle not drips but... It doesn't sound like a lot but running 24/7 it all adds up.

Perhaps running it for an hour a day would be better. Say 8 g in one hour each day to turn all the water over in a week.

Hope this helps.

Dylan

 

[And_Hef]

Well the idea was based on the fact that a natural river is constantly being changed over (like say the Amazon, where most of the tropical fish come from).

After doing some calculations of my own, here is what I think I will end up doing.

Starting with the current 20% per week water changes, you would need about .125 gallons per day (1/8 of a gallon, 1/2 a quart, 1 pint, 2 cups) to achieve the same. So if you maintained this steady flow you would not be changing out any extra water than you normally would with your weekly water changes (same water usage as you currently have). You would still need to do a gravel vac every so often (but as soon as the gravel is clean you can stop, instead of continuing to achieve the 20% water change), so you would still be getting the leftover nitrates out.

I guess the idea would be a constant water change (instead of all at once), and you wouldn't have to lug heavy 5 gallon buckets through the house to drain the old water from the water change, nor would it take so much time.

Assuming this system isn't 100% efficient, you could still do say a 5% water change with a gravel vac and maybe increase the flow a little to exchange a little more water than the 20% water change (say ramp it up to a 30-35% water change average).

The 2-3 gallons per hour flow rates were way too high. I am thinking 1/4 to 1/8 of a gallon per day (like you said a slow trickle).

I understand there are a lot of good things in the "old water", but nevertheless you need to get some fresh water into the tank and some old water out (to reduce the nitrate count).

 

[Wonderboy]

Now that sounds like a good plan to me! A constant water change happening throughout the week instead of at the end... well put.

You asked earlier: Will it work? Well, there's one way to know for sure...

Are you going to try setting it up???

 

[And_Hef]

Oops, I got my calculations mixed up. It would be (based off a 100 gallon tank) about 3 gallons per day or 1/8 gallon per hour. Still the same as a 20% weekly water change.

I also meant to say, you could always keep your current filtering system in place (maybe even back it down a little, say turn it to low instead of on high).

Yes, I am planning on doing this in a couple of months when we move to our new house and I setup the 90 gallon. If I get the time, I might start getting the equipment gathered and test it on my 55 gallon before we move.

Of course, I will keep my current filtering system in place and slowly back it off constantly checking the water parameters, and I will do a full write up as I go.

P.S. Both of you contributed tremendously in helping me figure out exactly how to active this, so thanks to both of you, Wonderboy and Dylema!

 

[And_Hef]

Additional ideas for the system... I would have a check valve after the filters to prevent a siphon (which may not be necessary if you have the inlet in the power filter or near the top of the water level). And have a float switch in place to turn off the water supply if the drain gets clogged and to turn on the power filters (or whatever backup filtering system you have in place).


I created a Microsoft Excel spreadsheet that will calculate the flow rate based off your tank size and water change percentage.

Send me an e-mail address if you want a copy of it.

 

[Wonderboy]

I'd love to take a peek: [email protected]

 

[And_Hef]

I'd love to take a peek: [email protected]

On it's way, let me know if you don't get it or if it doesn't work right.

 

[Wonderboy]

Works like a charm - Well done!

~ Wonderboy!

 

[andywg]

My only fear is the use of check valves and float valves. These things can fail. They will not always, but I always plan for the worst.

If and when I set up a constant water chane I will change a couple of things:

1) I would have a larger water change per week than 20%. I would probably have a 100% per week water change. Much easier, and no worrying.

2) Rather than relying on vavles, I would run it closer to a sump system, and so have the water pass over a weir into a chamber with a hole drilled which then runs to the waste water supply. This way, it would only be while the tank was being refilled that the water would be shed to waste, and if aeverything failed, all that would happen would be that the water change percentages go up.

Obviosuly these sorts of systems work even better on centrally filtered systems (such as a rack of tanks all connected to one sump). And my system would not require such careful monitering of trace elements as I do not grow plants.

 

[And_Hef]

Sounds like it might work all right, but let me see if I can follow what you are trying to do and why.

The float switch would be the exact same as you find in the back of a toilet. How often do you see those fail (personally, I have never seen one fail. I have seen some of the other stuff fail, but not the float switch). Again, I have seen and used hundreds of check valves and have yet to see a low pressure (say under 1000 PSI) fail. The hi pressure ones potentially can lock up, but it is still pretty rear. It is a simple concept, have a ball inside a tube where if it is pushed one direction it opens and if it is pushed the other direction is closes. If you are talking low pressure (meaning the pressure going the opposite direction you want to flow) there is not really a whole lot that can go wrong. But as you said, there is always that 1 in a billion chance; I plan on having a tiny pinhole just below the water line in the tank, which will break any siphon in addition to the check valve.

I was thinking of doing a sump type filtering system and having the fresh water dump into that which would also give me a place to have the float switch without it being in the tank.

1. I do not understand why you would want to do a 100% water change. For one it is not necessary. Two it is wasting water. Three it will cause more stress on the fish. Also you need to keep in mind, if for any reason your water company changes what they're doing to the water (say they double the amount of chlorine) you're filters might not be able to keep up and soon you have a huge problem on your hands (meaning you'll start having dead fish before you figure out what's going on). If you limit the amount of water coming into the tank, you might be able to catch major changes before a disaster. (that's not to say you couldn't have one even at 10% changes). I think at 100% per week you're going to spend too much money on the extra water without benefiting anything.

2. I don't think I'm following your design intent. I think my plan is somewhat like what you're talking about, but instead of having a physical sump, I would have the incoming water coming from the filters (instead of from the sump pump) and the waste water (through an overflow box) would be connected to a sink drain (instead of returning to the sump).

I don't follow how you're going to get any water out of your system (if you add water you have to take away water or your tank will overflow). Can you do a drawing or describe it a little more?

I am not saying your idea wouldn't work; I am just not following your idea.

I agree, I think a tank rack with a sump would be ideal for this type of setup (or one really large tank). Maybe like a retail store (LFS).

The trace elements in your tank are still needed for the good bacteria that keep your fish alive (just not in high amounts). Also, the may concern is the iron which I can simply look at the plants day-to-day say as I feed the fish to make sure there is enough (the plants will almost instantly show low iron levels with yellow leaves) in which case I add a simple drop of fertilizer and I'm done.

Works like a charm - Well done!

~ Wonderboy!

Thanks!

Do you plan on trying the idea?

 

[Tolak]

I've seen other breeders' setups that use a similar design. Either drip emitters, or a timer to fill, with overflows to drain. Often the water from a ro unit fills a 50 to 100 gallon holding tank to be reconstituted. Centralized air system for sponge & box filters, the only electric is a few lights, and heaters. You can get rid of the heaters if you have a seperate heating system for the fish room. It takes some time to set up, but the only maintenance is vaccing the bottom.

I have replaced numerous toilet float valves, I wouldn't trust them, not to mention they aren't drinking water safe.