Addressing Soft Water

@Paddyc  hi i'm looking for a calcium item but as i have some gravel already was looking more for a object to put in instead of the gravel you showed.

would you happen to know if these would work (amazon) 90-100G BROKEN CUTTLEFISH PIECES  -
can i over do it with calcium ?

A bit of googling says that cuttlebone contains calcium (about 85% according to one source) but i have not yet found any mention of carbonate. It could be that is it a different calcium salt in cuttlebone, and you need to add carbonate as well as calcium.

I have come across posts on another forum saying that the various sources of calcium carbonate have a limited effect on GH and KH, only raising them by about 11 ppm, which is less than 1 german degree. This person advocates the use calcium and magnesium chloride or sulphate for GH and sodium and potassium carbonate for KH. But he doesn't say how much to use 


I think I'd stick to chunks of coral or limestone and just have slightly raised GH and KH rather than risk overdoing it with the chemicals he suggests. If you make sure you change at least 25 of the water each week once you have fish, that will help too.

Can you find any Texas Holey Rock.... that will raise your GH from what I've read.

looks great but from the quick few searches for them the cheap 1s are just that cheap rip offs and real ones look like they are all in the £60 range which is more then i want to pay for a rock tbh.

Hi Luke,

Look at pg 1 on this thread http://www.thinkfish.co.uk/forums/new-fishkeepers/fish-tank-cycling-query/ and you'll see what a lump of limestone rock (Tufa) looks like - there's a pic of it in my hand - what's in my tank (54 litres) is about 1/2 of the size of this. Hope that's helpful.

@ColinB  not a problem shame though seeing as i liked the look of it a lot would have worked really well.

@fcmf thanks looks fine im guessing i could cover some of the base up to without a problem with gravel ? also  would you mind saying where you got it from as looking around for some (same as above) its very pricey and to big of a bag.

@Luke I went through a process of trying to control hardness a while ago, I have the oposite problem to you (I didnt know it at the time) but I have gravel that isnt inert in slightly acidic soft water and so I have increasing hardness levels that then dip when I do a water change I realy wanted to stay soft and acidic but the fish didnt appear to mind so I decided to pretreat the feed water with sodium bicarbonate. I used a plastic rubbish bin and stored next weeks water in it so I could add soda and then test the result- you quickly find how much is needed and dont have to test. So this solved the problem of sudden dips however it didnt address the basic problem and the acid water still disolved the substrate and levils continued to rise.
I think this will  be the problem you face if the tank water is able to attach whatever you use to increase hardness it will be a slow and constant process with dips when the water changes. I would suggest removing the 'hardening agent' from the tank and just pretreat if you want to get good control over the process.
I have given up on the buffering now but still use the storage bucket as I can dechlinate, airate and match water temperature. Ultimatly I will change the substrate but that is a major task so it will have to wait for another compelling reason to ruin the decor

thanks for the idea about putting it in with the filter just ordered the stuff to give it a try.