Drip water change systems?

[siklid]

Does anyone have any experience with drip water change systems, wanting to hookup 21 tanks to this type of system. Have watched a tonne of vids on YouTube and still not sure which way I should do it. If anyone is in Sydney that could help out and get things moving I’m willing to pay for your time and expertise. Would rather someone who knows about this fishy stuff than asking a plumber about it.

Daniel

 

Edited March 18, 2021 by siklid
Deleted text

[fishdance]

I'm in QLD not in Sydney but have been using drip water change for the last 30 years in 3 of my fish rooms (many many tanks, big & small). I've played with several versions and tweaked until I was satisfied but there are variations and you may have different priorities.

I use low pressure drip of mains water 24 hours every day through a standard 10 inch cartridge filter 5 micron ceramic then another 10 inch cartridge of carbon to remove chlorine & chloramine. The new incoming water displaces old aquarium water via an overflow  drain in sump.

* Changing to low pressure allowed me to remove all rigid expensive bulky pipes/joins and eliminated the damage & mess a leak at high pressure creates especially if your at work or on a week holiday. Some of the floods were ankle deep. 

* I use 4mm black micro irrigation tube which can snake around the room easily hidden with irrigation drippers to distribute adjustable water volumes accurately. Black tube preventing algae. Drip irrigation fittings have a wide choice and ridiculously cheap. The 5 micron prefilter reduces the clogging on carbon filter and drippers. 

* Constant 24/7 drip removed the complexity of a periodic drain then fill cycle. My experience is the constant drip being much better for fish, easier to heat in winter and minimises the risk of a bad mains water day (nitrite spikes, upstream pipe works, chloramine boosts in turbid catchment /heavy rainfall )

* Simplicity is best. The only trick is to have your main feeder pipe run low along the ground and the branches that feed your tank(s) go up.  So you can adjust each dripper independently and accurately. If you run the feeder line up in your roof space then down to the tanks, you have siphon and gravity imbalance issues. 

I use a dedicated water tap cracked slightly open to reduce the water pressure. My highest placed dripper is an extra one kept open as a pressure relief valve. Once set, I removed the water tap handle so no unplanned adjustments can occur. 

Another advantage of slow constant low pressure drip is the drainage line can be quite small if your fish room doesn't have floor drains. Even a 20mm PVC waste drain pipe can accomodate drips. 

Do have the drippers above the water line so you can visually check they are running. 

The carbon will fail very gradually (not suddenly) so you have many months to realise. The first few years I had a small tank of canary test fish. Their small tank would get totally water changed each day. Never had an issue so I changed to chlorine checking on the first day of each month. A 10 inch cartridge of carbon was dechlorinating 150 tanks - 25,000 L (in that room) at approx 20% weekly for 3 years comfortably. By that, I mean I calculate what percentage of a psrticular rack I want to water change each week and set the dripper to deliver that volume. Grow out tanks get 50% changes weekly. Holding tanks only get 5%. Nowadays, I don't chlorine check as I'm very familiar with my water & system. I just replace the carbon every even birthday (every 2years) which is far to early but easy to remember. On my bigger fish rooms with much higher water volumes, I make my own much bigger carbon filter as this let's me source a known grade of carbon. These get changed every 5 years (again just for the convenience).

Send me a private message with your phone number If you want more help as a phone chat is much easier. No offense taken if you decide a different drip method is better for your style of fish keeping. 

Winston 

 

Edited March 19, 2021 by fishdance

[adamgatt]

Hi Winston

Very interesting and detailed post. I am working on setting up a new fishroom and am also looking at automated water change options. Thanks for sharing the information!!!

[siklid]

Hi Winston, I appreciate you going out of your way to explain in such detail. I feel it’s helped immensely and the information on running the drip along the ground instead of up high I wouldn’t have even though about.

I’ll send you a PM with my details, thanks again.

[fishdance]

Hi Adam, yes planning a fish room can be exciting but it does help to know what you want. Hit me up if you want some suggestions as I know what aisle size, rack alignment, tank clearances, floor drain placement, electrical circuits, etc works best for me. (repeat - works best for me). However half the fun is working out these details for yourself I suspect.

While the drip water change should be kept as simple as possible, incorporating specific options to cater for individual fish keeping requirements is still possible. A single 4 liter per hour drip will displace almost 100 Litres every 24 hours or 700 Litres per week. That's an extremely slow drip rate visually for context.

Some of the things I have incorporated include having a storage tank for RO water, surge/wave dump tanks for oxygenation, a side circuit to external IBC pods to rotational grow green water (flush feed fish for natural colours), etc.

Below I have a 150 L sump used as fish harvest tank on a 9000L of growout system. To harvest, I pull the tanks central stand pipe and the fish end up in the sump. Because I wanted to keep the sump as small as possible (far undersized), I used an auto start & stop siphon drain. A siphon is able to power drain all excess water much faster than a gravity overflow drain from a sudden power outage and the sump will continue to run when power is returned. The lost water being topped up from the drip.

 

Edited March 22, 2021 by fishdance

[Link2Hell]

many thanks for the info Winston

this is a very good information for those wanting a fish room or to just make 

having a larger number of tanks more manageable

 

hope all is going well for you mate 

[adamgatt]

Hi Winston

I have been reading your post over and over again. It has some great info. I am looking at inline filters to take the approach you mentioned, straight from the tap to refill my tanks. I was just wondering if you could provide a link to the inline filters you use, or if you think something like this would be suitable?

https://www.ebay.com.au/itm/324712753931?hash=item4b9a636b0b:g:y-4AAOSwfrJg7T0i

Also wondering, how did you heat the water? Did you use an inline heater? I am considering using the right mix of hot and cold water to deliver the right temperature. I'd appreciate your insights into that. 

 

Edit - also wondering how you handled buffers from the tap? Did you dose tanks/systems every so often depending on the volume of water exchange? 

 

Many thanks!

Edited August 31, 2021 by adamgatt
Buffers

[fishdance]

Hi Adam, those filters are fine but any carbon holding container will do because the water pressure is low. You could use a DIY PVC pipe with screw cap ends if you want to self pack the carbon instead of having to buy more expensive replacement cartridges which don't hold much carbon. A compromise may be to use a self refillable cartridge container instead. This let's you choose the grade /quality if your picky.   https://www.clarencewaterfilters.com.au/product/empty-cartridge-refillable-10-inch-x-2-5-inch/ as an example, there is plenty of choice.

Don't get hung up on having to use catalytic carbon to remove chloramine, at slow flow rate any carbon will strip chloramine but the higher grade activated carbon (more voids, more initial sizzle) will go longer periods between refills. I have acreage so it's easy for me to recharge spent carbon or make my own with a fire pit /fireplace.

I wouldn't recommend 0.5 micron prefilter as it will clog much faster resulting in more maintenance, even chlorinated water has lots of gunk that settles out in low flow. I found 5 micron was suitable and a ceramic core more durable than cotton weave or paper pleats but don't be afraid to experiment. 

QLD doesn't get as cold as NSW. A slow drip of cold water doesn't shift tank temperatures noticeably as my daytime temperatures are warm and all my rooms are insulated. On tanks which get 50% water change daily, I clip in a 100m coil of the 4mm micro irrigation tube for winter and drop the coil into a heated tank so the drip water is warmed. Sort of a heat exchanger situation. Slow drip is relative but about one drip a second shifts a surprising volume of water over a week. You can use higher rate drippers or more quantity of drippers as you need. I forgot to mention do use Pressure Compensating drippers as these release the same set volume regardless of pressure fluctuations. 

I don't buffer my tanks. Coral chunks  are used to maintain hardness in some systems. Send me a PM if you want some ideas on auto dosing. I generally try to reduce workload and complexity where possible. The more tanks you have, the higher the chance of something going wrong.

Might also be an idea to contact Daniel as I helped him set up off forum. He was going to mix hot & cold water and having recently set up, he may have a different perspective. 

[fishdance]

I played around with liquid fertiliser dosing systems (for farmers) many years ago but depending on your requirements and expectations, I think you will find the incoming tap water will vary from week to week so that complicates issues even if your dosing system is accurate. 

The most reliable low tech method would be to set up a water holding tank to pre mix the water then use that as a reservoir to supply your drippers. If you have height, put the reservoir up high and gravity drip. You should maintain an airstone to constantly mix. A few large scale marine keepers use two reservoir IBC tanks one above the other. The bottom is the mixing tank with easy access to pour in salt mixes. When dissolved, it's pumped up to the top holding  tank for use (gravity feed). 

If you don't have height, use a large powerhead or continous pump running 24/7 to push feed the drippers, returning the excess water back to the reservoir which will keep your reservoir mixed.

[adamgatt]

Many thanks again Winston for sharing your knowledge. I was originally planning to have large storage tanks/drums outside and then pump in from them (that's what I do in my current setup). After doing more research though and reading your posts I am now likely going to go straight from the tap with the inline filtration as you have described.

I just got most of my supplies delivered today to build the stands and run the drainage/overflows. I'll share some progress and the end result back here as I progress with it. Thanks again.

[Link2Hell]

@adamgatt don't forget to take pics and document it as I expect an article for the magazine 😁

[adamgatt]

No worries, Chris @Link2Hell. I have been filming my progress and Jason has been putting it on YouTube every so often. I've finally finished the building works and have started with the fun bit, the fish stuff. 😎 I've really enjoyed the planning and designing of it too. Can't wait until it is done so that I can get some additional species. 

[Link2Hell]

thats excellent that Jason has Vlogged it as now you can do it as a talk also 😁

[adamgatt]

Hi all. Here's a look into where my new fishroom is at the moment! I've had an issue with my air circuit that has set me back a bit, but I think I have it sorted now so hopefully will be able to get all tanks running soon. At the moment I am going to be using the top row of tanks as my water reservoirs for water changes until I can sort out the end game water change system!

 

 

[Yeders]

On 01/09/2021 at 9:39 PM, fishdance said:

I forgot to mention do use Pressure Compensating drippers as these release the same set volume regardless of pressure fluctuations.

Hi All,

From what I understand, these drippers are a set L/hour rating, so they aren't adjustable; you just need to buy different rates. From my understanding, they come in 2, 4, and 8L/hr. Is that the case?

If so, I might need to rethink my current set-up as I have a few hold tanks (like, 80L) that should have their water changed, but at 2L/hr, it would turn over in <2 days which is faster than necessary. The alternative would be to set that specific line on a timer/solenoid and run it only every few days. But that adds complexity which should be avoided... am I right? 😂

[fishdance]

An irrigation specialty store should have 0.5 LPH pressure compensating drippers. The pressure compensation is mostly for convenience as different dripper heights are typically used in a fish room or you may have a large fish room or the mains tap pressure may fluctuate. If your tanks are at similar heights or you don't mind manually adjusting (and measuring) your drip  rate then use normal drippers as these can be turned right down or completely off. Just be mindful of preventing pressure build up longer term. A bleeder dripper over sink for example could be used.

Another suggestion is to link multiple 80L tanks together and use a 2 LPH for this set of tanks. Just be creative, it's not an absolute science.

To increase your KH, I would add a small amount of crushed coral. Idiot proof method of providing buffer that's slow release.

[Yeders]

Thanks for that!

Indeed, I'll have drippers at ~3 different levels. Given that I already have adjustable drippers (non-PC), I'll set them up and measure the water collected over x time period and adjust accordingly. I think that I'll be able to determine a rough LPH, from drops per second (or mL per second/minute) and adjust. Then look at how things change when house members are showering, etc. I'll see if I start pulling out my hair as slowly down some drippers might blow out others!

Would there be benefit into adding a pressure regulator before or after the 5micron & GAC filter? eg, a 300kpa : https://www.bunnings.com.au/pope-300kpa-pressure-reducer_p3121926
So then, the pressure is constant at the source?
Again, thinking out loud, depending on the number of drippers, 300kpa might be limiting? (probably not for my limited set up, but for others to consider).

Thanks for your help.

[fishdance]

Older houses (30+ years) often have tap pressures of 700 kPa while newer houses have 500 kPa according to my plumber who is excellent. It's quite easy to measure your water pressure if you have a pressure guage - just screw connect it to any threaded tap. That said, low pressure irrigation fittings would struggle over 150kPa I suspect. If no external leaks occur, everything is good! No pressure measurement needed.

As previously posted, I reduce my mains water  pressure simply by dialing down a dedicated brass tap to a mere trickle with the carbon filter downstream. You can also effectively reduce water pressure with a longer narrower diameter supply line to drippers. Do use barb adapter fittings (not threaded) and hopefully your polypipe needs to be heated to push on. The mindset is low pressure - slow flow but ever constant and you will be surprised how much water change can be achieved. Not having to touch or adjust things  builds in reliability which is why PC drippers are better.

I've had issues with that particular Bunnings pressure reducer the once and only time I tried it. It's only plastic. 300 kPa is still too high.

I have used non-PC drippers before and the water volume/rate changes for each dripper as the water pressure changes. So whenever you open up or close other drippers, they are all affected. I only had 60 tanks on that set up but it was a constant battle if precision is needed. If water temperature during winter isn't an issue, you may be fine even if 100% water changes daily? 

All tanks on a central sump can be considered one tank. Similarly, it's very easy to connect several vertical tanks with a power head, just drain top tank into the tank(s) below. Before I bought a glass hole saw, I used water bridges to connect tanks horizontal.

I'm sure you will work it out. Just solve each issue as they arrive.

Edited October 5, 2023 by fishdance

[Yeders]

On 20/03/2021 at 4:26 AM, fishdance said:

The carbon will fail very gradually (not suddenly) so you have many months to realise. The first few years I had a small tank of canary test fish. Their small tank would get totally water changed each day. Never had an issue so I changed to chlorine checking on the first day of each month. A 10 inch cartridge of carbon was dechlorinating 150 tanks - 25,000 L (in that room) at approx 20% weekly for 3 years comfortably. By that, I mean I calculate what percentage of a psrticular rack I want to water change each week and set the dripper to deliver that volume. Grow out tanks get 50% changes weekly. Holding tanks only get 5%. Nowadays, I don't chlorine check as I'm very familiar with my water & system. I just replace the carbon every even birthday (every 2years) which is far to early but easy to remember. On my bigger fish rooms with much higher water volumes, I make my own much bigger carbon filter as this let's me source a known grade of carbon. These get changed every 5 years (again just for the convenience).

@fishdance Hi again!

I'd really like some help with this!

I've been doing some math on activated carbon / granular/ cat etc.

It's very hard to get adsorption profiles for GAC regarding chloramines.

Was your fish setup in Brisbane? Do you know if your water report now, (avg. 3.2ppm chloramine) was similar to what it was back then?

And, do you know the absorption limit of the GAC you used?

 

Keeping the math very short, from what I've read, GAC only absorbs 0.5mg of chloramine per g of carbon, and at 3.2ppm of chloramines, and 380g of carbon in a 10" cartridge, its only 60L of water treated.

The amount of water you're saying you treated with a single 10" cartridge is massssivvveee, eg. 2.5kg of chloramines treated with 380g of GAC

There must be something I'm not accounting for! 

[fishdance]

I'm in Brisbane.

I won't be able to help with the theoretical chemistry calculations but I suspect the slow flow rate - longer dwell times through the carbon makes a difference. Or perhaps the 5 micron ceramic prefilter extends carbon efficiency. I don't worry about chloramines as it can't be present if chlorine is not detected.

I prepack my own carbon cartridges. They make modules to suit a standard filter housing which can be filled with whatever media you like. This allows me to save money, maintain quality control of carbon and pack more densely.

What I suggest you do is set up your carbon filter at the flow rate you will require and test weekly. That's the best way to know for sure. I use the swim pool chlorine test tablets which show pink if chlorine is present. Deeper hue of pink means higher levels of chlorine.

While no chlorine is best, a trace amount is still fine for many months. You will have plenty of warning.

If you want longer intervals between carbon replacement, improve the grade of carbon or add another carbon filter (in series) or get a bigger carbon filter. Easy to DIY a screw cap 100mm PVC pipe as long as you wish (as carbon holder) or repurpose an aquarium canister filter, or scavenge small swim pool filter (check behindyour local pool store) as this is low pressure.

After I first posted my experiences, I googled drip systems and was blown away at how much information is available online and how detailed some videos are etc. I felt a bit embarrassed explaining when so much knowledge is easily available. No wonder these discussion forums are dwindling. Anyway, always happy to help.

[fishdance]

Remembered a conversation with an experienced pool guy many years ago. It is possible to calculate chloramine level with the Palin (DHP) tablet test results but it was tedious and subjective. Especially as we are only interested in a zero result.

Zero free chlorine indicates zero chloramine.

I did a quick google to find something similar

https://www.kuntzeusa.com/knowledge/chloramines-and-dpd-1

Essentially wait longer for the test result and repeat the test several times for consistency 

Another thought I had was more and more companies and water filter resellers claim only catalytic carbon will remove chloramine which sadly is a blatant lie. Similar to having to change cartridges more frequently to be effective. Upselling using fear and ignorance.

I use activated carbon (not catalytic carbon). The finer the particle/granules and the higher the activation level, the more effective the adsorption rate. Old school "sizzle" test is a reliable guide. The level of activation is simply the void ratio due to the firing temperate used to expell gas to create voids. It's easy in theory to recharge used carbon if you have a fireplace or firepit (and a thick steel pot).

Don't get me wrong, catalytic carbon would remove chloramine more efficiently BUT if it cost ten times more it would need to be ten times more efficient to be economical. Especially if you buy activated carbon in 5kg bags.

[Yeders]

Thanks for all of your suggestions.

Yeah I've also looked online, lots of ideas and different ways to do things, but many dont get into the detail.

Yes I was going down the 90mm drain water PVC route for the carbon with the micro pre filters.

Fairly easy to do. I just wanted to get the theory right first. But I might not be able to do that... We'll see! I might do some experiments on a reduced scale. That should work...

 

One thing worth mentioning... You mentioned that if free chlorine is zero, then chloramine is zero.

As far as I knew, Free chlorine only detects chlorine. Total chlorine tests also detect chloramines. 

I'm not familiar with the pool test kits with the tablets though. Is that total or free chlorine? It would be good to see how different your tap water total chlorine is vs your local water report. Mine seems to be pretty similar.

Both the Brisbane and Sydney water reports differentiate between free chlorine and total chlorine. When you test your water, your test needs to include total chlorine. I have some test strips that test both total and free. And as somewhat expected, I get 0 free and 1ppm of total.

I'll let you know how I get on with the carbon saga.

Cheers!

[fishdance]

I rarely test anymore but I was using DPH 2 tablets (total chlorine).

I recommend you use 100mm DVW pipe over 90mm stormwater for durability.

Also for context, if your dripping say 10% of your tanks weekly, the 1.0ppm becomes less than 0.1ppm which is fine even for fry. With time, you will be able to let your fish behaviour tell you if there is an issue.