Any idea what's going on with my water?

[rubarb]

Hi everyone,

I have a 6x2x2 planted tank with co2, tonnes of plants and some driftwood. I was really really happy not long after I set it up to see that my ph sitting at 6 and kh and gh really good. However, I tested my tank the other night and much to my disappointment my ph was sitting at 7.6! Not very happy. My fish and plants are still going strong but I really want to get my ph back down to that 6 mark.

Does anyone have any ideas how to soften the water without using ph buffers or adding any more wood?

Any help would be appreciated.

Thanks

 

[Evan]

What is the ph and kh of your tap water?

 

[ed seeley]

And what substrate are you using? Have you added a plant substrate like Eco Complete as I believe this raises KH and pH?

 

[chris1932]

It sounds like as the tank has matured and you have done water changes the tannins that lowered your pH have worn off. I would think that you have quite a bit of alkalinity in your source water. Buffering the water to decrease the pH is only going to make it harder on a kh scale or add phospate. You may want to add more c02 during the light cycle, and airate during the evening.

 

[rubarb]

Thanks for the replys, I use ADA Amazonia 5mm and 3mm black rocks. My tap water is quite normally around 7-8 and thought with the wood it should stay at around 6. kh is 160ppm and gh I am not sure. My co2 unit is terrible, i need a new regulator and my 2l bottle lasts about 2 weeks [pretty sure that isn't normal but anyway i've had this debate with the lfs owner a couple of times]. So will have to wait until i get my co2 fixed etc. and see what happens from there

 

[tjudy]

With a KH and pH that high expecting driftwood to drop the pH all the way to 6.0 is probably inrealistic. What are you keeping that you want a pH that low? You mentioned that all the fish and plants look great...

 

[Anubias Design]

Agree with Ted

Ted hit the nail on the head. If everything looks great, why mess with success? If you have nice, hard water with plenty of carbonate sources in it, the CO2 is superfluous in my experience. Your plants will grow just as well without it and you won't have as great a likelihood of algae problems developing later. Be sure to use a good iron-heavy plant fertilizer on a daily basis. The idea is to keep the water nutrient poor so that there are enough nutrients for the plants to use in about 24 hrs. In that situation, the plants will outcompete any algae present for the nutrients and you should not have any algae related issues.

If you really want to lower the pH, try adding peat moss to your filter and putting some almond or oak leaves in the tank.
Mark

 

[rubarb]

The only reason I would like the softer/low ph water is really only for my discus & apistos. Mind you my pandurini's are showing fantastic colour. but my viejitas are taking a really long time to fully colour up. But I always tell people if there is nothing wrong then don't do anything... perhaps i should take yours and my own advice. Cheers for the help guys.

 

[ed seeley]

You need the CO2 to grow a wide range of plants. Not all plants can get their carbon from biogenic decalcification. Some will grow ok with the CO2 levels present without injection, but their growth will be limited by it and the instability caused by it can trigger algae growth IME.

Adding nitrate and phosphate won't cause algae and limiting nutrients won't prevent it as they need such tiny amounts to grow. And if you limit nutrients that much what do your plants use to grow? They need far more nutrients than algae. Dosing with too much iron can also cause it to precipitate out of solution and cause heavy iron deposits within filters and substrate, especially if it isn't chelated.

IME the easiest way to grow plants (but not the cheapest by any way) is to use injected CO2, lighting about 2wpg, ADA Aquasoil (as a nutritious substrate) and a light daily fertilisation of both macro and micro nutrients. This will work very well with soft water that the fish will love as the aquasoil also reduces the KH as well as feeding the plants. The downside (apart from the cost of the CO2 kit and the Aquasoil) is that the Aquasoil will leach ammonia for the first 2-4weks so you need to do some large water changes at first and fishlessly cycle the tank for a while.

 

[tjudy]

In my experience most 'soft water' fish, including discus, thrive in harder water. There are exceptions, such as maybe Apisto. diplotaenia. Successfully breeding soft water species in hard water is another issue. I keep and grow fish in my tap water (250 mS conductivity, pH 7.6, KH 12) with no problems. I worry about hardness and pH if I want to get them to spawn successfully.

 

[jose_vogel]

You said that you injected CO2, but as important as this is how the CO2 is dissolved.

If you dissolve it inefficiently, it´s like you don´t have CO2.

 

[rubarb]

My co2 unit isn't very flash. pressurized 2l bottle goes into the bubble counter/diffuser (dupla combo). My co2 gas only lasts two week. The fish seem to be fine and the plants are growing Just slower than normal. I am going to hire a probably a 5kg bottle from BOC(gas company) they'll do it for Au$65+/- per year and fill it up when req. that is going to be a cheaper and more efficient idea. rather than fill up 2l @ $25 every two weeks. I have a quad 54w T5 lights over my tank. I am glad to know that my fish should do well and appear to be doing well dispite hardish water. I wouldn't know how to calculate w/gal :S

 

[ed seeley]

I have a quad 54w T5 lights over my tank. I am glad to know that my fish should do well and appear to be doing well dispite hardish water. I wouldn't know how to calculate w/gal :S

If you've got 4 54W T5s then you've got 4 x 54 watts of light = 216 watts.

A 6x2x2 tank should hold about 144 gallons (6x2x2=24cuft x 6 gallons per cuft = 144g).

Then you just divide watts by gallons, so you have 216 / 144 = 1.5wpg.

While that's below 2wpg on a tank that size it should be plenty as larger tanks seem fine with a lower wpg. If you haven't got them yet then some good reflectors on the tubes should be fitted to get the best out of them, after all it makes sense to get as much of the light you're paying that electricity for into the tank!

On a tank that size a fire extiguisher or other CO2 cylinder would certainly be more economical and give you much better results. To diffuse the CO2 on a large tank like that you might want to use a CO2 reactor outisde the tank rather than a glass diffuser inside. They're very efficient and you can DIY one easily so cheap too!

 

[rubarb]

Thanks for the calculation!! I currently have my lights suspended diy style about 10-15cm or so from the top of the tank and plan to move them a little closer to the top of the tank as my crypts seem to be growing up towards the surface rather than in a nice clump. But my tank is finally starting to look how I plan and when my mate comes over hopefully in a the next couple of weeks with is digi slr hopefully I can get some decent photos posted.

As for the diy reactor... sounds like it could be fun. Will have to do some research on it but overall and for some reason I got a diy bug atm. will explain all that in detail when I get my materials to build my new breeding racks and get my sump built. It's going to be tricky for me but looking forward to it!

 

[MikeR]

If you've got 4 54W T5s then you've got 4 x 54 watts of light = 216 watts.

A 6x2x2 tank should hold about 144 gallons (6x2x2=24cuft x 6 gallons per cuft = 144g).

Then you just divide watts by gallons, so you have 216 / 144 = 1.5wpg.

While that's below 2wpg on a tank that size it should be plenty as larger tanks seem fine with a lower wpg. If you haven't got them yet then some good reflectors on the tubes should be fitted to get the best out of them, after all it makes sense to get as much of the light you're paying that electricity for into the tank!

On a tank that size a fire extiguisher or other CO2 cylinder would certainly be more economical and give you much better results. To diffuse the CO2 on a large tank like that you might want to use a CO2 reactor outisde the tank rather than a glass diffuser inside. They're very efficient and you can DIY one easily so cheap too!

FWIW, I built a CO2 reactor using an old calcium reactor designed for marine reef tanks. I exchanged the aragonite with bioballs to aid in the diffusion of the gas as in recirculates in the chamber. The CO2 is controlled by a Pinpoint pH controller that controls the microvalve on the main CO2 tank.

This system has been running a 150 gallon tank with loads of plants that is exposed to direct sunlight for about 6-8 hours a day and is heavily fertilized 3 times a week. The CO2 tanks are 10# and last for months on a densily planted tank.

Mike