Can I make blackwater using my tap water?

[Mazan]

Mm well I don’t have matten filters, I will try Mike’s method, I didn’t have enough bits of UG filter left so will get one tomorrow, I found what I think is a suitable bag for the peat pillow. The peat should help to make the water more acidic theoretically…

A <column design> is the most effective, because the fraction collected at the bottom doesn't mix with the source water, so it's not equilibrating. That obviously takes some time and effort, so what Mike suggests (forcing water through the peat) is another good solution.


In my experience, it doesn't take a lot of alder cones to very darkly stain the water, so it is nice to have a concentrated stock to control the dilution. It's safe to put any amount in your tank, depending on how dark you want it. It won't affect your pH or TDS much, but it will add tannins/humic/fulvic acids, which are thought to be beneficial.


I think there are too many variables to answer, so it will take some trial and error. I would just measure periodically and pay attention to the rate of change. If you do find a regime where the pH lowers, assume that the rate of change will taper. Once it stabilizes, the pH might rise again after that.

Many thanks, I added a little of the alder extract to the tank, and will just experiment with the peat.

The male pike cichlid has been displaying occasionally to the female, she sometimes spreads her fins at him in return, but it usually ends in a chase. Other times I see them more relaxed together for short periods. But they are fish that hide a lot anyway, especially the female, there are plenty of hiding places and often I don’t see them at all.

 

[Mike Wise]

This is how I use a 'peat pillow" for making blackwater. I have 2 tanks, a 55 gallon for straight r/o and a 29 high for peat water. The 29 has a full coverage air-driven undergravel filter plate. I take the pillow and fill it with enough dry peat to make a layer about 2"/5cm thick. I cover the filter plate completely with the pillow and weight it down with large inert rocks, basalt in my case. I then let it run for a week with r/o water and check the pH (sometimes) and e.c. I will mix straight r/o and peat water to suit each species needs when doing water changes. I will refill the peat water tank with more r/o without recharging the peat. Only when the water become too pale do I replace the peat. I've been using this method for decades. Now I don't regularly test the water often. I judge what I need by eye.

 

[Mazan]

This is how I use a 'peat pillow" for making blackwater. I have 2 tanks, a 55 gallon for straight r/o and a 29 high for peat water. The 29 has a full coverage air-driven undergravel filter plate. I take the pillow and fill it with enough dry peat to make a layer about 2"/5cm thick. I cover the filter plate completely with the pillow and weight it down with large inert rocks, basalt in my case. I then let it run for a week with r/o water and check the pH (sometimes) and e.c. I will mix straight r/o and peat water to suit each species needs when doing water changes. I will refill the peat water tank with more r/o without recharging the peat. Only when the water become too pale do I replace the peat. I've been using this method for decades. Now I don't regularly test the water often. I judge what I need by eye.

Many thanks, that is very clear explanation, I will try to set this up this afternoon. I am sure the rocks from our river are inert as the water is so soft, and I have some in my other ranks. My peat water container is smaller I think, but anyway I’ll see how it goes.

 

[Mazan]

Sorry another quick question, do you heat the water change water to the same temperature as the tank?

 

[anewbie]

Sorry another quick question, do you heat the water change water to the same temperature as the tank?

I have a system that pretty much ensures the new water is within a couple of degree of the tank water. More precisely in the basement i have a large ro storage unit with a heater in it - naturally some of my tanks are warmer (like discus tank @ 82-83) than others like the winkelfleck (76ish); so there will some modest error. I think i keep it around 78.

I started doing this when i killed a pair of rams doing water change during the winter and not paying attention to the replacement water temp. Back then (after the ram death) i would fill a 40 gallon pail stick a heater in it and do the water change the next day so i evolved as i've become a wee bit more clever in my old age. Now i have a well pump hooked up to the storage container and just open a valve to get warm ro water.

 

[Ben Rhau]

I kept my RO water at room temp, and given the needs of my fish and the size of the water changes, it never changed the tank temp by more than 2 or 3 degrees.

 

[Mazan]

Yes, I will be keeping it at room temperature, I don't really want to add yet another heater! As its just for one tank I'll just check the temperature difference and heat the water change water if necessary.

For my other tanks I just run a hosepipe from a warm water tap and turn down the gas water heater so that the water is within a couple of degrees of the tank temperature.

 

[Mazan]

I started doing this when i killed a pair of rams doing water change during the winter and not paying attention to the replacement water temp.

I also did this accidentally a couple of years ago. One of the water pipes in the house had got blocked and the water pressure dropped so that the gas went out and I didn't realize the water was coming out cold until the tank temperature had dropped from 26 to below 20 very quickly, all the angelfish and some tetras died. The Laetacras, Otocinclus, pleco and some other tetras all survived, I felt awful, and now always constantly check the temperature when the tanks are filling.

 

[Mike Wise]

My water change tanks are in my fish room, which is heated to ~77°F/25°C. No tank heaters at all. They fail much too often for me.

 

[Mazan]

Mm yes heaters are unpredictable, I have had new ones stop working after a few months, and some I have had for years with no issues. I don’t have a fish room, my (currently) 5 tanks are in 3 different rooms, so I do need to use heaters unfortunately.

 

[anewbie]

Mm yes heaters are unpredictable, I have had new ones stop working after a few months, and some I have had for years with no issues. I don’t have a fish room, my (currently) 5 tanks are in 3 different rooms, so I do need to use heaters unfortunately.

I'm not sure how warm the room is vs the tank but if you use a large pail (30 or 40 gallon) to hold the water overnight even without heater it will be warmer than faucet. You can also help with the temperature difference by dripping the water into the tank over several hours - of course in this case you are using the aquarium heaters to warm it. I don't know your setup or prices in your locality but in the usa rubber-maid pails are quite sturdy and not too expensive. Of course they do make thinner cheaper pails that might burst - so the ones i refer to are the brute series. I also don't know the condition of your floors and if a pail with 300 lb of water would be an issue.

Obviously 20 degree difference is a big issue but 5 degree is probably close enough.

 

[Mazan]

Well the peat water container is in the same room as the tank, and that room does not normally get very cold, especially at this time of the year. At the moment the temperature of the peat water is 21C (about 70F) (yes much warmer than out of the tap) and the tank is nearly 27C (about 80F). If I do small water changes often I think it will probably be Ok without heating, or I could heat it slightly bit by bit in a big saucepan. TDS in the peat water has increased to 44….

 

[anewbie]

Well the peat water container is in the same room as the tank, and that room does not normally get very cold, especially at this time of the year. At the moment the temperature of the peat water is 21C (about 70F) (yes much warmer than out of the tap) and the tank is nearly 27C (about 80F). If I do small water changes often I think it will probably be Ok without heating, or I could heat it slightly bit by bit in a big saucepan. TDS in the peat water has increased to 44….

The tds thing also drives me crazy - some of the my tanks have tds in the low 20's (discus and a. sp blukies) but others are in the 60s or even as high as the 80s (wolli and ladisalo tank 2); of course they all get the same water and have the same simliar setup. The wolli and ladisalo tank 2 do not have any stone and have the same substrate as the tank in 20s - so of course something is adding tds - for now i will just chalk it up to plant decay

Either way the wolli breed just fine (though my understanding is they are a less picky fish than the blukies but you can treat this as hersey unless an expert states otherwise.

The discus tank of course has the most going on and is 180 gallons plus another 40 or 60 gallon in the sump which is closer to your setup on the opposite extreme they blukie tank only marginally 20 gallon and probably closer to 15 gallon when we consider substrate et all.

 

[Mazan]

So the undergravel filter has definitely helped. I did change the small air pump I used initially for a water pump that circulates the water through the peat more effectively, and I added a bit more peat. Before the water was staying stubbornly around pH 6.5-6.6, always the same, and the same as the tank. This morning it had gone down to 6.2 (maybe not totally accurate as I am using liquid tests, but at least moving in the right direction).. The tank was due for a water change so I used the peat water and refilled the container. I will have to do several small changes as the peat container is not very big, only about 40l / 10 gallons. No worries with temperature as there was only about 5C difference today. TDS in the tank has increased to 31 though (it was 55 in the peat water), and the water is very cloudy, I hope the filters will clear it before long. In the peat container I have now attached a sponge filter to the pump intake so hopefully this will help a bit. I think it is the type of peat as the one I was using before stained, but did not cloud the water.

 

[Mazan]

Today the peat water was down to pH 5.5 (approx). I changed another 10 gallons in the tank. I suppose this way pH and temperature changes will be (very) gradual at least...

This time I put the peat water into the top filter not direct to the tank, still cloudy but not as bad as last time.

 

[Mazan]

I have changed the water in the tank for peat water a couple of times since I last posted. I haven't needed to change the peat yet, the water with peat is still going down to pH 5.5 in a day. But the tank is staying at 6.5 still and the TDS has increased to 37, I suppose that is still quite low. Today it rained hard! the first time in months, we have been having the worst drought ever recorded here. So I collected a tub of rainwater, it is pH 6 and TDS 12, so I may use this along with the peat water tomorrow for a bigger water change. It doesn't look very clean, but only ran off our roof which is unglazed red terracotta tiles but does have a fair bit of dirt and moss and plants growing on it, I don't think there should be anything harmful though?

 

[MacZ]

But the tank is staying at 6.5 still and the TDS has increased to 37, I suppose that is still quite low.

Completely fine. The fact that pH measures the concentration of H+ ions is just proven: There are not enough H+ added to push pH down and so the tankwater diluted them.

 

[Mazan]

Do you think t will be Ok to use the rainwater? Power will be off between 9.00 -1300h today so I won't be doing the water change until later. It doesn't look clean but I can't think that it would have anything harmful in it...

 

[MacZ]

Run it through some mechanical filtration and if you want to make sure maybe run it through active carbon as well.

 

[Ben Rhau]

How big are the water changes, and how often?