Dear all
I have a question re how soon /how much to feed fish in my new pond - it's a small sleepers pond that holds roughly 4000 litres:
And apologies in advance about the long post - I wanted to give all the details so people can give me informed advice.
More details:
Fish load - 2 tosai koi measuring just over 1 foot, 2 very large golden tench measuring about 2 feet (1 female which is very bulky/heavy), 1 golden tench measuring 1 foot, 2 small golden tench measuring 6 inches, 2 shubs measuring 8 inches.
Holding tank - you can see the holding tank in the first photo above - 2000 litres QT with Oase Biotec 5.1 filter and a 3000 lph pump. All above fish had been in the tank for 5 months, putting some good growth over summer. Immediately prior to moving fish, the tank water tested 0 ammonia, trace nitrite (slightest purple tone), 40ppm nitrate, 9 drops KH, water temp 12~15 degrees. Fish were fed once every other day given the cooler temp. I have about 20 litres of Siporax media matured in the tank for 5 months - about 5 litres I 'stuffed' inside a meter long 3" outlet from the filter, and the rest I placed in fine mesh bags and dangled on the shaded edge of the tank above a strong air stone attached to an Oase diffuser.
New pond construction - 1.03 meter wide x 3.3 meter long x 1.3 meter deep or 4500 litres if filled full. It's the biggest size we could fit into the garden without disrupting the balance of paths around the patio/lawn. Depth is 0.8 meter in the ground, and 0.5 meter above which is held by 5 rows of 100x200 sleepers (treated and painted outside) and existing masonry retaining wall . Due to the long shape, for the bottom 3 rows sleepers I put in 1m long 20mm rebar every 0.4 m around the 3 walls, except the masonry wall. The sleepers sit on 0.4m deep concrete collar and the rebar goes through the collar into the ground. Box weld liner. It is copped with untreated douglas fir sleepers on all sides - with bolts installed to hold child safety net.
New pond filter - (second hand) Oase Screenex 36000 (like Screenmatic but its a static sieve vs the auto rolling sieve in the Screenmatic version), Oase Aquamax 11500 pump. I know this pump is a bit over the top for my small pond, but I want a higher water flow given my fish stock and how fast the 2 tosai koi can grow in subsequent seasons.
Move details:
- Day 1 - In the Oase Screenex filter there are 4 cannisters with zeolite in them - I took out zeolite and put in instead (what I believe is) the most mature Siporax media (from the holding tank QT outlet pipe). I also moved the Oase air stone with diffuser (according to Oase this diffuser helps with bacteria colonisation) I soaked the zeolite in salt water for several days with twice a day salt water changes, and store it for emergency use. I filled the new pond with 10% tap water with dechlor, tested for chlorine (DPD4 tablet - no pink tone), and 10% water from the holding tank. I then moved the 2 smallest 6 inch golden tench to new pond. I then backfilled the holding tank with tap water with dechlor.
- Day 2 - Seeing the 2 small golden tench behaving normally, I proceeded to move the basket of plants from the holding tank to new pond. I then moved the 2 shubs, and 1 koi from holding tank to new pond. I also transferred additional 20% water from the holding tank, and also added 20% tap water with dechlor - tested for chlorine. At this stage new pond is 60% to full water capacity. I also backfilled the holding tank with tap water and dechlor and tested for Chlorine.
- Day 3 - water test showed 0 ammonia and 0 nitrite. All moved fish appeared normal and actually more active than in holding tank. I moved the remaining fish (2 large golden tench, 1 medium golden tench and 1 koi) all into the new pond, and transferred water from holding tank until new pond is 80% to full water capacity. I also moved all remaining mesh bags with Siporax media to new pond (also dangling on the edge next to air stone and in the shade). I decommissioned the holding tank, and took the filter sponges out, washed thoroughly in tank water, then put them in mesh bags also in the new pond. I'm hoping all these dangling mesh bags would provide good healthy bacteria to avoid new pond syndrome when the liner walls begin to mature.
- Day 4 (today) - All fish behave normally. water test 0 ammonia and 0 nitrite. 7 drops KH which I thought is a little on the low side given next week is forecasted to rain heavily all week - so added some bicarb to bring to 9 drops KH, also added some Kusuri clay. Water temp 14 degrees.
I previously planned to move fish over the course of a few weeks. But what I realised was - as I took more and more 'furniture' from the holding tank (air stone, diffuser, and the plants) - the tank became quite bland and the remaining fish no longer had all the 'cover'/hiding places they had before and appeared more shy. Also seeing their mates got netted one by one was stressful... Last, I thought there was merit to accelerate the move when water temp is still decent (12~15 degrees) with a few more days of warmer than usual weather forecasted. I fear it will get colder very soon and wanted to give fish/filter more 'warmer days' to settle in.
My question is - how soon should I start to feed the fish (and how much/frequently) assuming water test 0 ammonia and 0 nitrate again tomorrow (Day 5)? The smaller fish that got moved first weren't fed for 5 days and the bigger fish weren't fed for 4 days. In the holding tank there was a thin layer of velvety algea all around the walls which they were snacking on. The new pond obviously has just butyl liner that is brand spanking new!
All fish had been very well fed throughout summer/autumn. 1 koi and the biggest female golden tech got so thick and I wonder if they were egg bound. I plan to fast them from late Nov when first frost hit and water temp drops to less than 8 degrees - all the way till March.
Any advice would be really appreciated.
Namo Amituofo