Hi, haven't been on here for a while, I've enjoyed a few years of trouble free fish keeping. However, I'm completely stuck at the moment and need some help.

I have 2 tanks, one large, one small, and they both are having problems, even though they've been fine for ages (years) The strange thing is they are having different problems. Any ideas appreciated!

Tank 1):

Large tank, 4 goldies, 1 shubunkin. Has been running for a couple of years, problem free. I recently cleaned it out, replacing all of the water and I also changed more of the filter medium than I should have. (60-70%) I may have been over feeding them too and since I did this change I've been feeding them about hlaf as much as before. Apart from that, there are no other changes to their tank. No new fish/plants etc.

Ammonia: 0.25 three days ago, 0.25 two days ago, 0 today (not fed for 2 days)
Nitrite: 0
Nitrate: 10
Ph: 7.0 three days ago, 7.2 two days ago, 7.2 today.
Ph from tap: 7.5
Test kit: API Drops
Tank size: 450L, running 2 years with current stock.
Filters: Jewel Jumbo
Water change: 100% every 2-3 months.
Fish: 4 goldfish, 1 shubunkin, aprox 15-20cm long (body only)
Water additives/conditioners: Stress coat when adding new water.
Medictaions: None
New fish: None
Food: Fish flakes, occasional frozen trests (bloodworm, brine shrimps, peas)

We noticed that the fish were starting to gulp (heavy breathing) a couple of weeks ago, so I did a full tank clean (100% water). Cleaned all the gravel and replaced a lot of the filter. It was very messy as I think I've been over feeding them. Since then, I've fed them about half as much. However, they've started the heavy breathing again and also they're occasionaly rubbing themselves on the gravel. They are also very stressed and panicy. One is more stressed than the others somewhat.

I stopped feeding them 2 days ago and they've calmed down a little and the breathing has also calmed down, but they're not back to normal yet.

We noticed today that 2 of them seem to have the odd red patch on their body. (scals size or less) This may be from the scratching on the gravel - I don't know.

Here's a small video of them gulping... (Quicktime)

http://www.webblies.co.uk/fish.MOV



Tank 2):

Small tank, 1 Weather Loach, 1 Bitterling. Has been running for a couple of years, problem free. This tank gets a 80% water change every couple of months. The only new thing to happen recently is I added a rock, from my sisters tank which has been running fine for ages, that's covered in a very pretty long haired algae (2 inches long)

Ammonia: 0.25 three days ago, 0.25 two days ago, 0 today (not fed for 2 days)
Nitrite: 0
Nitrate: 80 three days ago (I did a 80% water change after doing this day's tests), 10 two days ago (a day after the water change. I did another 80% water change this day), 10 today. (36 hours after the last water change)
Ph: 8.0 three days ago, 8.3 two days ago (a day after 80% water change. I did another 80% water change this day) , 8.2 today. (36 hours after the last water change)
Ph from tap: 7.5
Test kit: API Drops
Tank size: 60L, running 2 years with current stock.
Filters: Fluval 3
Water change: 80% every 2-3 months.
Fish: 1 Weather Loach, 1 Bitterling
Water additives/conditioners: Stress coat when adding new water.
Medictaions: None
New fish: None
Food: Fish flakes, occasional frozen trests (bloodworm, brine shrimps, peas)

In this tank, we noticed that the Bitterling kept swimming in the filter stream whereas he always used to simply rest/hide behind the filter when not active. We also noticed that he's become slightly agressive towards the Loach - which he's never done before (specially at feeding times).

On seeing the PH level, I did an 80% water change and tested the tap water to make sure it wasn't the cause. The next day (24 hrs later) I tested the water again to find it had jumped up again, to 8.3 this time. I did another 80% change and on testing it again (36 hours later) it was 8.2 again. I really can't understand why it keeps jumping like this.

I'm very confused. I have one tank that it dropping in PH and one that is growing in PH (rapidly). I have 7 very unhappy fish and zero clues.

Very confused, any help appricated!

hi and welcome back to kokos one thing that does stand out is your once every few month water changes ..in this time very bad bacteria can grow and nitAtes can climbs and can become dangerous..goldfish even in small numbers need a weekly waterchange and gravel vac in an established tank..so many bad stuff and dorment parasites can fester in gravel and reek havoc I am not an expert at diagnosing your fish but I would assume by the flashing and sore that they have flukes and possibly a bacteria problem going on ..wait to see what the others have to say good luck my fingers are crossed for you and your fish oh yea I couldn't see your video