Electrically controlled valve for cold water supply

[AsleepInYorkshire]

I hope as you read you're safe and well.

Yesterday afternoon I popped my head into my 12 year old daughters lounge. I was shocked to see her aquarium was on the brink of an algal bloom. I say shocked because she carries out two fifty percent water changes every week. She has a 260 Litre (60 gallons) tank. If I may please, hasten to add, that in order for her to be able to carry out this mammoth task I have set up an semi-automatic system which means she has only to turn a few valves to both empty and fill her tank. Also I didn't want her first footsteps into the world of fish-keeping to be one of "chores". We checked the water parameters and I couldn't believe what they were. The nitrates were 20ppm and the phosphate levels were off the chart, so exceeded 1.8 ppm. I couldn't work out how they had become so poor. We did a 65% water change immediately. We also removed all the rocks and the "contaminated" sand at the front of the tank and left them in a mild bleach overnight. I cleaned all the glass sides of the tank. We finished at 10pm. Today we have carried out 2 more 65% water changes. I've not replaced the rocks or the sand [just] yet, albeit I have rinsed them thoroughly to ensure no bleach residue exists.

Upon completion of the water changes we tested the water again. No difference. Then the penny dropped. We tested our tap water and it was 10ppm nitrates and (as the tank test) this was off the scale for phosphates so exceeding 1.8ppm.

When we first set up the tank we tested our tap water and it was 1ppm nitrates and 0.1ppm phosphates. Neither of which caused any concern. However, and quite naively I have assumed these levels would be a constant. And we all know that assumption is of course the mother of mistake .

We've left the lights off today and nudged the Co2 up just slightly. If I have understood the internet correctly low Co2 helps algae? The algae we are dealing with is a green hair algae and had grown to lengths of about 3 to 5cm. There was also an amount of cyanobacteria (green slime) and I've removed all of that too.

I'm in no doubt that the underlying problem is our tap water. I'm also convinced that we can cope with the nitrate levels and even reduce them as we have used a specific media that provides a full cycle. When it was first used we saw our nitrate levels fall from about 10 to 1ppm. Apart from turning the light off I've no other "immediate" control over the algal/cyanobacteria growth. However, her aquarium is heavily planted and she has an LED light which enhances plant growth (Fluval Plant 3) so turning the light off does feel counter productive in the long term.

Which brings me to the reason for this post. I think the most viable option available is RO(DI) water. Hopefully I have reached the right conclusion. I was hoping to set something up that is no more complicated than the current water change system I have set up for her.

I envisage using an RODI unit on a timer and sending the clean water straight to the fish tank.

1. Inside the fish tank will be a pump to remove the water
2. That pump will be turned on through a timer to remove a set amount of water each day
3. The RODI unit will be connected to the incoming mains water
4. Standard practice is to send the RO water to a sump unit and then to pump out of that unit into the fish tank using an electronic feedback to prevent over-filling. The sump uses a float valve to cut off the flow from the RODI unit.
5. There isn't room for a sump in our "set-up"
6. I want to use an "electronically controlled in-line valve" downstream from the RODI unit to turn off the flow.
7. The valve will be controlled by an electronic "top-up" monitor within the fish tank

Can anyone please tell me what the valve is called please?

Thank you

AiYn'U

[servodude]

If it's simply on/off, I would call it a solenoid operated valve or an actuated valve.The latter widely available to use in central heating systems.

RVF

Agreed!

Sounds like you want a two-port normally closed momentary solenoid valve
- that would open to allow flow when you energise it

If you want to control it the other way you'd have a normally closed (and energise it to stop)
- and if you want headaches you'd use a latching one (where you have to reverse the drive signal to switch direction)

- sd

[Dod101]

Interesting. Nothing to do with your question but I wonder if your water company would be interested in your readings? My daughter works for Scottish Water and they would be I think. They test water constantly and would probably pick up on this sort of thing and maybe do something about it.

Just a thought.

Dod

[pochisoldi]

Find someone who is scrapping a washing machine and recover the solenoid operated water valve and while you are there the pressure operated water level sensor(usually located above the drum and has a clear pipe which goes to the lower part of the drum.), and the internal rubber pipes. The solenoid valve will usually have an integrated mesh filter and a standard washing machine hose fitting on the input (hack a hose to suit!).

Using a Honeywell CH valve is possibly overkill, expensive and bulky. A solenoid valve will shut immediately and is a guaranteed seal when shut. A spring return motorised valve will take several seconds to close, and may be liable to weep (not an issue in a heating system where both sides of the valve are "wet" anyway)

PochiSoldi

[AsleepInYorkshire]

Interesting. Nothing to do with your question but I wonder if your water company would be interested in your readings? My daughter works for Scottish Water and they would be I think. They test water constantly and would probably pick up on this sort of thing and maybe do something about it.

Just a thought.

Dod

In the US many water companies encourage fish-keepers to ring in with any results that indicate an issue with water quality. The nitrate levels are something "we" can cope with as the filter media completes a full nitrogen cycle. However, phosphates levels above 0.5ppm can and often do create algae. Small amounts of algae we can cope with as we don't object to cleaning the glass every now and again and we have a little clean up crew of three Otocinclus that tidy up too . It's when the phosphates get above 2ppm that algal blooms start to become prevalent. I think water companies add phosphates to drinking water? I'll make a call and see if I can find anything out from YW.

AiYn'U

[Dod101]

Interesting. Nothing to do with your question but I wonder if your water company would be interested in your readings? My daughter works for Scottish Water and they would be I think. They test water constantly and would probably pick up on this sort of thing and maybe do something about it.

Just a thought.

Dod

In the US many water companies encourage fish-keepers to ring in with any results that indicate an issue with water quality. The nitrate levels are something "we" can cope with as the filter media completes a full nitrogen cycle. However, phosphates levels above 0.5ppm can and often do create algae. Small amounts of algae we can cope with as we don't object to cleaning the glass every now and again and we have a little clean up crew of three Otocinclus that tidy up too . It's when the phosphates get above 2ppm that algal blooms start to become prevalent. I think water companies add phosphates to drinking water? I'll make a call and see if I can find anything out from YW.

AiYn'U

You will probably also find an analysis of the 'normal' levels on their website. My son lives on the Antrim Coast in N Ireland and when I visited him at first I could not understand why my stomach got upset within 24 hours of being there until I realised that they are living on limestone and the calcium levels are off the scale which, as the website helpfully explains, can cause stomach irritation. Locals are used to it.

I live near the Highland Spring bottling plant and my tapwater is more or less Highland Spring so I am very sensitive to changes in the water content.

Dod

[GrahamPlatt]

Hi Dod,

As you live near the Highland Spring plant, I thought you might find this interesting:
https://www.bbc.co.uk/sounds/play/m000fn8t

[DrFfybes]

I saw your earlier post about setting up the tank.

I'm assuming with all the complicated kit it is a Marine one? I've had Tropicals since about 1974 and much of what you describe is unfamiliar to me.

Either way your problem isn't a technical one, it is more likely overfeeding or overstocking (or both). You should only need quite small water changes to keep a tank healthy. For Tropical I've always stuck with one inch of fish per gallon in an established 'community' tank, a lot less with Cichlids etc or a new setup or a breeding tank.

Hair Algae is a bugger though - only really removed by mechanical means - those plasticised metal panscrubs work on ornaments, and if it is on the plants just throw them out.

Paul.

[jfgw]

I would certainly not use a central heating valve for this purpose. They are not designed for mains pressure and they may not shut off 100%.

Last time I bought a new washing-machine valve, it was £6. Buy a new hose from a spares shop, not a shed. I have known the plastic nut to split on the shed ones.

If you want to use a lower voltage for safety, 24V valves are available for different things, e.g., https://www.amazon.co.uk/DIGITEN-Soleno ... lp_pl_dp_3 .


Julian F. G. W.

[AsleepInYorkshire]

I saw your earlier post about setting up the tank.

I'm assuming with all the complicated kit it is a Marine one? I've had Tropicals since about 1974 and much of what you describe is unfamiliar to me.

Either way your problem isn't a technical one, it is more likely overfeeding or overstocking (or both). You should only need quite small water changes to keep a tank healthy. For Tropical I've always stuck with one inch of fish per gallon in an established 'community' tank, a lot less with Cichlids etc or a new setup or a breeding tank.

Hair Algae is a bugger though - only really removed by mechanical means - those plasticised metal panscrubs work on ornaments, and if it is on the plants just throw them out.

Paul.

AiY"t"n'U

[AsleepInYorkshire]

Thank you for all your replies. I've been planning everything and tonight (overnight) we run "Operation Mermaid" .

Yes. The item I needed was a solenoid valve. However, I also needed a few other items too.

My daughter was very clear about what she wanted for her fish. She wanted them to live in a heavily planted environment and she wanted to have colourful fish. It's reasonably easy to get plants to grow in an aquarium if they are planted far apart and they don't compete for the various resources they need. When there's a lot of them they begin to compete and some of the smaller low lying plants don't thrive. At this point it's usual to introduce a light source which simulates sunlight. These lights have come on in leaps and bounds in the last five years. Not only that they can be set to simulate dawn, dusk and different sunlight conditions experienced around the world. Now throw in a little fertiliser and some Co2 and the plants will thrive. But at the same time if the level of phosphates in the water is above 2-3ppm then the chances of algal blooms are high, almost inevitable.

Our tap water is high in phosphates. And after one algal bloom we had to turn the lights off. And the plants don't thrive. The fish don't have as natural an environment as can be offered. And viewing, the most important part is limited to a few hours on an evening. And the need to clean the glass of algae increases.

What started out as a vision becomes a chore. And water changes only serve to increase the problem.

I found a solenoid valve..

The Autoaqua ASOV is explained here.

I dropped a small pond pump in a discreet corner of the fish tank. I've yet to add an analogue hose timer to control the mains water entering the RODI unit and I've also got to add some battery operated hose timers to the outflow from the pump(s) to prevent syphoning when not pumping. I use the term pumps as there are now two pumps, one for each tank

Standard practice for RODI water is to collect it in a container. To then "remineralise" it and then add it to the fish tank. My plan is to add it to straight to the fish tank. I don't plan to do weekly water changes. I plan to do much smaller water changes, but daily. Once each tank has been filled with "phosphate free" water then small water changes each day will keep it that way.

The first photo below is our lockdown project and that is the tank that we are running Operation Mermaid on tonight.
The second photograph includes her other aquarium. Obviously the bits and bobs you can see are work in progress. And for those of you with a really keen eye the three plant pots in the "green" aquarium aren't permanent.





AiYn'U