CO2 levels and algae hell. Please help !!!!

V

Vyper

AC Members
Dec 26, 2004
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Manchester, UK
Hi All

I really need some advice, as I'm being given conflicting information and terminology thats fairly unfamilar to me so I'm hoping someone can make sense of all this and put me straight.

In a nutshell over the past 3 weeks I've had an infestation ofg Black beard Algae which has plagued my tank, originally I was told phosphatess in the tap water were the cause of the outbreak, however my tank is fairly heavily planted and I was worried about removing phosphates as I figured they were needed for healthy plant growth. I have no idea how to even determine my phosphate levels or if its even worth doing ?

I then had a look round the internet and posted an article on here in the general fereshwater section and basically came to the conclusion CO2 was the problem, or lack of it. And that adding a CO2 system would sort the algae problem as it would allow the plants in my tank to compete for the nutrients in my tank that the algae are using.

OK everything sounded easy at this point, add a CO2 system, job done. So I rang my LFS shop and now here comes the personally confussing bit, I was told a CO2 system would help but this can make the water acidic, at the moment my PH is about 6.5 and I know I dont want it going any lower, so then the guy said I needed to increase my KH (totally lost here) and that would stop my PH from dropping, he said I'd ideally want a KH of 3 ????. I then asked ok assuming I have a high enough KH how do I tell what the right level of CO2 is ?, and he said if my KH was 3 and my PH was 6.8 then my CO2 level would be right ?

Finally the LFS said I should also remove my air stones completely as the plants would provide the required oxygen and adding airstones removes CO2, aparently by adding airstones I'm actually harming my plants and the general condishion of my tank.

So I'm at a loss people, do I get a CO2 system and risk lowering my PH, is there anyway proper way to see at a glance CO2 levels, what the hell is KH I've been told its a PH buffer but how do I get KH to the right level, and should I remove my airstones ?.

Please help

Incdiently my tank is 50g and consists of 3x 36" bulbs (white) and 1x 30" blue bulb. My stocking levels are 6 dwarf gouramis, 3 clown loaches about 15 platinum tetras and added yesterday 8 flying foxes which aparently eat BBA ???
 
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i am also new and i hope i give you the right info. if i dont someone will give you the right info.

this is a chart it figure out your co2 lvl.
http://www.aquabotanic.com/charts.htm

this link explains KH and PH how they work together
http://www.csd.net/~cgadd/aqua/art_plant_co2chart.htm

ok so hear is the deal. first of all dont buy a co2 set up from lfs it willl prob be a lot of money. i just got one from a guy used for $100. you can do it even cheaper then that. KH is like a buffer to the PH. co2 will lower KH which can make your ph go lower.

here it talks about raising your KH lvl. i searched really fast dont know how good this is.
http://www.rexgrigg.com/waterchem.htm
 
so Baking Soda will raise my KH huh? interesting very interesting
 
Yeah I noticed the baking soda thing too, my PH keeps dipping low.

Anyway further to my info this morning I went to my LFS today to get some water tests done to try and determine whats cauing my Algae, heres the results

Ammonia - 0
Nitrites - 0
Nitrate - 20
PH - 6.3
KH -0
GH - 8
Phosphates - Stupidly high, aparently theres tons in the tap water in the UK

So first things first I got some KH tablets which aparently raise my KH, I've been told to get it to 3, so I'm adding these tablets 6 at a time (aparently 3 tablets gets 100 litres to KH 1) so I've been told to take it slowly and gradually increase this level, so I'm gonna give that a try over the next few days.

Right as for phosphates, this sounds more tricky aparently I can't just get some phosphate remover and I'd never be able to stick enough in the tank to combat the phosphate levels after water changes etc, does that sound right ?.

And I've been told ideally I should use RO water, sounds easy enough but there priced at about £130 and aparently dont come as standard with your bog standard tap adapter, they come with some hose adapter which I'd have to convert somehow. I really wish I could just buy something like a barrel with some kind of filter in it which purified my water, I hate the idea of having my water running full blast for 6 hours or some other riduculous lenth of time to make about 285 litres of water. Seems almost too much effort for purifed water.

One bit of good news is my flying foxes seem to be keeping the algae in check, and now I've got some KH I can now consider a CO2 system which aparently should improve my plants health no end and allow the plants to compete for the nutrients in my tank. I'm conducting a CO2 test now to see what level that is I'd imagine its rock bottom right now, so I'm seriously considering getting a CO2 system as soon as I get my PH and KH sorted.
 
To safely raise KH and keep it steady you need to add crushed coral to your filter,though you could probably get away with putting it in the tank in a nylon bag.

The crushed coral will dissolve in the acidic water slowly rasing the pH and KH. pH will raise to around 7.6 - 7.8 and KH to around 4 - 6.

You'll then be able to safely add injected CO2. A drop of 1 pt in pH will let you know you're in the proper CO2 range.

So after the pH hits the mid 7s and KH is 4 or so the injected CO2 will drop the pH back to mid 6s and the KH will still be in the safe range.

You'll still need to watch the crushed coral to make sure it doesn't run out but it should last a long time. The baking soda will dissolve quicker and be removed with water changes, so you'll be adding baking soda all the time. The crushed coral will keep KH/pH bounce at a minimum.

Also RO water is a bad idea for freshwater fish and planted tanks. It removes necessary minerals and electrolytes that the plants and fish use.


Did they tell you what ppm of phosphates are in the water? I dose 2 ppm a week into my tank not counting what might be in the water.
 
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I dose 6 ppm of phosphates every 2 days into my planted tanks. I have not seen any new algae growth in months. Phosphates do not cause algae this is just a big myth. 90% of algae is caused by poor or no CO2 and the other 10% is caused by inadequete fertilization like too little phosphates.

Get some crushed coral to take care of the kH and remove the air stones. They are not needed in a planted tank. Keep some surface disturbance though. Low pH will not harm your fish. My tank swings from a pH of 7.2 to 5.8 every day and my fish have never shown any stress. When the lights are on, I drive the pH down with CO2 to 5.8. At lights off, the CO2 turns off and the pH gradually goes back to 7.2. If pH swings caused fish health problems then water changes would be toxic. In the wild some fish endure pH swings of 3 points daily. I agree RO water is not needed and you are better off with your tap water. Since your water has high phosphates, you have one less thing to worry about when you dose nutrients.
 
Cheers guys that the best info anyones given me so far, the LFS strictly told me that the phosphates were the cause of all my algae problems, infact they went as far to say phosphates were bad as they were a micro nutrient and plants only use macro nutrients so phosphate were only good for encouraging algae growth !!!. Anyway I've seen a setup that looks very cheap, it says its for tanks up to 100 litres but mines 180 litres so do you reckon if I add 2 to the tank this would do the job. Heres the link

http://www.aquatics-online.co.uk/Z404002.asp#product3069

I've just done a CO2 test with an indicator i bought and it turned blue indicating I had hardly any CO2 in the aquarium, so if you guys think the above system would work for me I'll get 2 of them.
 
Baking soda will raise kH, but only temporarily. Crushed coral an a nylon filter bag, in your filter will buffer up your kH and protect against pH drop. The problem is that the coral will not start to show it's affect for 1 - 2 weeks. Therefore, baking soda can be a useful measure if you're in a hurry to buffer the pH for the short term.

You don't mention the size of your tank, but a 20 gallon tank can easily accommodate a cup of coral to buffer pH. You'll have to convert your liters to gallons to figure out how that equates for your purposes, but coral although a great buffer when up and working, is so slow to kick in that a cup or more will not 'over-dose' the tank. When you reach 3.5 - 4.0°kH you are good to go.

The amount of Sr (strontium) in crushed coral is minute and should not be considered dangerous. I know 100's of folks using coral to buffer and none of their fish have neon-like (except some tetras) colors to my knowledge:).

Based on your post, I'd say that most of what the LFS told you was good advice. Possibly you mis-understood what he/she said with regard to phosphates.
An excess of them can cause devastating results in an aquarium, and my UK friends have told me for years that the tap water over there is notoriously loaded with P in many areas. They get around this with either RO water or dosing no P and matching N and K to balance their nutrients. But balancing P with light and the other macro elements will not cause algae issues.

As to the BBA problem......pick up some Seachem Excel to use in conjunction with your CO2 injection and that will help a lot in combating this stuff.

Len
 
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Cheers, its a 180 litre tank by the way.

I've just added 6 KH tablets and my PH has gone from 6.3 to 7.5 at the last check, I thought KH was supposed to protect against big PH changes, and its done exactly that, why is this ??
 
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