New Aquarium Cycle/PH Problems

Hello, Alex, and welcome to the forum.

Sue is the cycling guru, so she'll be along soonish to help you out. Have you read the fishless cycling method here?

You're not going to able to change your water down to an acceptable level..... actually, it's not water, it's liquid rock!

You're far better off making your own water by installing an RO machine and mixing in the required amounts of minerals to give suitable conditions. There's an paper here to get you started.

Alternatively you could keep Rift Valley Cichlids as your water's OK for the right ones.... I forget which lake!

Since your arm has been twisted into a fish-in cycle, you have no other option. At least you had a tank when the goldfish arrived - my sons turned up from the fair with 4 which spent the first night in a mixing bowl (and one didn't make it)

250 litres is a great sized tank for goldfish. Fair fish are always common goldfish or comets, which means they have a single tail fin. Fancy goldfish have double tails, which means they aren't as good at swimming. If you mix the two, the commons and comets will always get to the food first, which is why it is not advised to mix them.
Member fcmf used to keep goldfish so she'll be able to help with their needs.

It is not a good idea to mix goldfish and tropical fish. The temperatures needed for tropicals won't do the goldfish much good. If you want tropicals you will need to find a new home for the goldfish. In this case, the simplest thing might be to give the goldfish to someone who has a goldfish pond rather than set up another large tank for the goldfish.

Your liquid rock is a bit hard even for goldfish. fcmf should be able to help you with the the levels usually recommended for goldfish. As you have found, RO water is the easiest way to reduce hardness of both types, and the pH should drop as well. There are 2 ways to use it. Either use just RO water and add remineralisation salts to put some hardness back or mix RO and tap water in whatever ratio gives the required hardness. You will need to use this RO + salts or RO/tap mixture at every water change so always make sure you have access to RO and have some salts always in stock if you use that method. To begin with, you need to change the water gradually. Too big a change at one go will harm the fish.


As for cycling, what had you done before the goldfish arrived? Even a fish as messy as a goldfish won't make much impact on a 250 litre tank. You may find the ammonia and then nitrite rise slightly but with such a huge volume to dilute it they may not go up very much and normal water changes would keep the levels under control. But be careful about adding more fish. Get new fish slowly. If you intend keeping goldfish, get one at a time and check the ammonia and nitrite levels for several days after each one.

But if you decide to go tropical, you have the chance to do a fishless cycle right to the end.

Following my long post about goldfish, I thought I'd post a separate query about your water test kit in general - is it a liquid-based one? It sounds from the readings as though it is (in which case that's fine). The reason I'm asking, though, is because I find the test strips tend to provide artificially much higher readings for KH and GH and slightly lower readings for PH than the liquid-based kits - I find the test strips accurate for the other tests but not KH and GH and so I thought I'd check with you.

Your water supplier should also have the facility on its website to input your postcode and give you hardness readings; let us know what it says and the unit of measurement (eg degrees Clark, French, German). Between that, and your own water testing results, we'll be able to offer further advice, depending on how you decide to proceed ie the goldfish or tropical route.

Good plan to farm out the goldfish.
You can then do a full fishless cycle using your tap water while you're preparing for your fish of choice and preparing a plan for your water. It will be the first fill after cycling that will be the real pain, after that it will just be your water change water.

The hardness is easy to deal with. As you have 20° tap water then a 50:50 mix with RO or rain water will bring that down to 10° which is fine for most tropical fish. It's the pH that is the worry.

I take it from your water parameters that you live in the South East (if you're UK based) and I used to live there, too. However, my tap water had a pH of 8.8 and a GH of 16º German. I used to mix my tap water with rainwater (or RO from my Local Fish Shop if the water butts got empty or too manky) in a 50:50 mix and this gave me tank water of 8º GH with a pH of 7.4

Can I suggest you try a small 50:50 mix of rain water and tap and see what numbers you get?

Can I also suggest that you consider a heavily planted tank with real plants as the benifits they bring will mean less water changes.

We like helping people..... it makes us feel useful!

I looked for an expire date but I cant find one anywhere so no I don't think so.

100% rainwater was around 7 a bit darker then 7 but lighter then 7.5.
50/50 rainwater was I believe a little less then 8.5 maybe 8.3

The desired PH is 6.8 but that seems impossible right now. will RO water and rainwater yield the same results?
If so I think the plan will be give goldie to my brother then do a massive water change to get it as close to 7 as I can install a heater and buy some pure ammonia and start the cycle again.

I have considered cichlids but my heart is set on angels and plecs and I think even cichlids might struggle with a ph of 9.5 no?

Also im not on a meter just paying monthly do they waste water even when not in use or something :S?

Edit: apparently we are on a meter.

I, too, am worried about the pH of 9. Can you get some of your tap water tested at your LFS for a second opinion?

The thing about rainwater having a pH of ~7 is that it's completely unbuffered, so you would need to 'build' your water using, for example, this to give you the minerals you need in the water, and this to buffer your water around a neutral value. I've never done this, so you might need to trawl around t'interweb to find more info.

You would also need the associated test kits. The trouble with this is, once you've gone down this path there's no returning..... and for a 250litre tank it might get a bit pricey.

Since cycling goes faster at higher pH and higher KH I would suggest doing nothing to the water until the cycle is finished. You will have a few weeks to decide exactly what you want to do.

Start the fishless cycle. If there are any bacteria from the goldfish, they'll still be there.
Given the cost of doing large daily water changes, a fish-in cycle is not a realistic option for you.

Once you have fish, make sure you always have some mineralised RO on hand in case of an emergency water change. Even if the fish are fit and healthy it is not unknown for the fishkeeper to accidentally drop a whole tub of food in the tank, or a young visitor to feed the fish something totally inappropriate.

(The way to prevent the first is to measure the food out somewhere not on top of the tank  )

Stocking ideas so far

Plec bristlenose  x 4 60cm                 23-27dc               
Angelfish x3 45cm                            24-28dc              =183cm  25dc
dwarf neon rainbowfish x10  63cm    22-26dc         
Blue grourami x1  15cm                     23-28dc            

Not quite sure on how many CM i can go up to in a 250 but the calculator says 400cm with an external filter.

Obviously wont be adding all that at once and not till cycled, not sure what to add first tho.

Also to note the PH has risen by .5 overnight no idea how as i have driftwood and sand in there i exspected it to drop to 6.5 6.8 maybe it was because some of the tap water was in the sand mmh.

Also to note the PH has risen by .5 overnight no idea how as i have driftwood and sand in there i exspected it to drop to 6.5 6.8 maybe it was because some of the tap water was in the sand mmh.

mmm - patience you must.