Hi all.

I posted my results for my first week's fishless cycling and there was a slight drop in the pH level from 7.5 to 7. Rabbut replied to my post and said it wasn't good and advised a water change. As it was late I left it until this morning and it had gone back up to 7.5. but tonight when I got home from work it had gone down to 6.5 so I've just completed about a 70% water change.

The pH has now risen to 7.5 again. What do I need to do now? I've not added any ammonia or done other tests yet because I wanted to ask advice first. The only thing I've done is add the dechlorinator.

Any advice would be gratefully received. Thank you very much.

Mine crashed last week too. Check your Ammonia levels. If its 0 take it back up. If there is still ammonia in there wait for it to process then carry on as normal adding ammonia when it hits 0. Im sure Miss Wiggle BTT or Waterdrop will fill you in when they next log on

This post has been edited by stormy78: May 19 2008, 07:47 PM

I thought everything was going well until this happened, oh well I suppose's it's a learning curve!!! Hope everything is going ok with your tank now.

Any chance you've got a KH test kit Jazee? What you need to do is either pick up one of these at a LFS or have one sent from the web. As usual a liquid-based kit is recommended.

If your KH (Carbonate Hardness (sounds all scientific but really its all over the earth because of eons of animals making shell for themselves in all those ancient oceans and this I think is mostly what all those shells are made of.. in fact this is also what limestone is after all those little shells have been squished for millions of years.. isn't that interesting!)) is low, then its much easier for your pH to crash during fishless cycling.

If your KH is decent, an occasional water change should take care of things, but if you have low KH then there are a couple of approaches: one is baking soda and the other is crushed corel. Baking soda is quick acting but is usually only recommended for fishless cycling situations, whereas crushed corel is slower to act but then requires less attention in the longer run and it is the better option for the different situation of wanting to change KH and pH after you have fish.

OK, that's the summary so let us know..

~~waterdrop~~

Hi waterdrop, thanks for the info. I had seen people mention KH before but never really understood it until now. I'll pop and get a KH tester kit tomorrow. What kind of reading should I be hoping for? What is classed as good and what is classed as low?

It's like being back in a science class at school, I was never much good at that either!!

Oh heck, thought I could get away with a day before I had to type that in..

In most kits, KH is measured in German degrees of hardness, one of four older scales (I guess we like old stuff in the fish hobby!) So you can picture that Calcium Carbonate is molecule of Calcium, Carbon and Oxygen etc. in your water and it can be measured in parts per million (really milligrams per Litre since its a solid in a liquid).. just like other things we measure and there are 17.9 mg/L in one German degree of hardness. So each degree we are going to measure is a nice significant step up in hardness. Each step upward we take increases our ablility to "buffer" our water against rapid changes in pH (pH stands for ""P"ower of Hydrogen, isn't that wacko! and is the measure of our free hydrogen atoms or how acid or basic our solution is) so.....

0 = no hardness, extremely soft water
1-4dH = Very Soft
5-8dH = Soft
9-12dH = medium Hard
13-18dH = fairly Hard
19-30dH = Hard
above 30dH = Very Hard water

OK, so here's my rule of thumb: If your tap water has a KH of 0-3, you might need to treat it via baking soda or corel if you are getting frequent pH crashes (drops to 6.2 and below) in order to help along your fishless cycle. If you are doing that then it is also the range of KH = 0-3 that I think is a your sign to treat again and bring your KH up higher. When I say a "good" KH, I'm just talking about a higher one, like somewhere in 5-10, which in fishless, means you've got many more days of peace before a water change and/or recharge of baking soda (if that's what you're using.)

Let me repeat: Whenever I write this stuff its important for anyone reading it to realize that its a special case for a small number of people. This is people who have unusually *soft* water. If you've got a KH of 4 or above I would say you probably don't need to worry about anything other than to occasional water change if the fishless cycling process brings your pH down to 6.2 or below. And remember, the goal of all this is fishless cycling is just to help keep the pH up there in the upper 7's or 8's because that's what helps the bacteria grow faster. Most people with pH that doesn't drop to 6.2 or below can ignore all this and just fishless cycle like our normal fishless article!

Oh, and Jazee, often the KH test is bundled with a GH test also, which is fine to have as an extra but not really a test that gives us any action items for the processes we are talking about.

~~waterdrop~~

Thanks waterdrop I really appreciate all of the information.

I'd just throw in some baking soda for now. If the pH crashed once, it will do it again during the cycle. The KH is IMO only in need of measuring strait from the tap once, so you know what it is like from there. If it is below 3dH, add some crushed coral to your filter to raise hardness for you. If it is higher, it should be fine for fish unless you inject CO2. After the initial test, the KH becomes more of a curiosity test unless you want to breed fish
You need about 1/2 a hand ful of coral to achive 1-2gH of aditional hardness in about 20g of water. Rince it regularly under the tap or it will be covered in bacteira that will stop it from disolving and keeping the hardness up.

HTH some
Rabbut

never knew that!!!! take it cos the 'p' isn't a chemical part of the compound that's why it's written in lower case not in caps like the 'H' for Hydrogen....... always wondered why you wrote pH like that you know.

anyway, as waterdrop has said you should be aware what your KH is, however it may not be criticial. it's well known that the cycling process drives pH down, a pH crash and subsequent stall of your cycle is almost to be expected during fishless cycling. Just monitor pH and if it keeps dropping keep doing water changes to bring it back up. Do get a KH test kit though and measure it, because the crash may be indicative of a larger problem which may need some rectifying, relativley easily done if you need to, best done with no fish in the tank so it's good to identify it early if possible.

pH stands for potential of Hydrogen Not Power

'potenz' even ... invented by a guy who wanted to test his beer

Potenz in english means Potential

Well its been passed around both ways for years but I agree that "potential" is more accurate historically.

I had another pH drop so as you all advised I did another water change and as I didn't have any crushed coral under my kitchen sink I resorted to baking soda!! It seems to be stable now at 7.5 as before I started and hopefully I can get on with my fishless cycle! Thanks again for all of the info. becky

Hi Becky,

It sounds like you didn't find a KH kit yet, not surprising as they are less common. Glad the baking soda helped out. Keep track of exactly what and when you use it and if you have any problems/questions just keep your thread going.

~~waterdrop~~

I have been out today and purchased a KH and GH testing kit. I had to get a Nutrafin test kit as they didn't have any API's.

The GH test kit came out at 200 which is right at the top of the moderately high section (101-200) over 200 is classed as very hard.

The KH test came out as 100mg/L which in the description say excellent buffer capacity.??!!

I was hoping someone would be able to tell me what to do next as all this is completely confusing me. My pH dropped to 6.5 again today so I've done another 50% water change and added a tablespoon of baking soda.

I'm still doing my fishless cycle, my ammonia is cycling in 12 hours but my nitrite is still high and hasn't dipped yet.

Thanks in advance for your help, becky

not sure on the conversion from mg/l to dkh but it certainly sounds like your KH is just fine, which is very curious as the pH keeps dropping. are those readings from the tap water or the tank water?

can you give us details of all the decor etc in the tank incase there's anything that's tinkering with this all

As with Miss Wiggle, I can't work with hardness measured in ppm, I need it in dKH before it makes sence

You usualy want about 4-8dKH in a tank with fish, to prevent pH swings, but not raise the pH through the roof. You however are fishless cycling, thus you will want the hardness higher, as nitrate is going to rise above "normal" levels, and it is acidic and thus will pull the pH down. For a fishless cycle, I'd look to get the KH to arround 12-20dKH, to prevent the pH dropping. The ammonnt of KH you need will depend on what your nitrates are running at

All the best
Rabbut