i am the proud owner of a goonch (yarrelli) that i picked up around march last year.
over the last year i have run a sort of experiment with my goonch and i figured i would share some of what i have been doing and my findings as i have gone along. the main focus is the best way to keep them, but rather than reading through the hundreds of thread (i have read lots) about how people's goonch have just died and try to work out why, i figured i would take a slightly different approach and go my own way.
so let start at the beginning.
originally my goonch was in a squarish tank, ex coral display type, in doors with heating (set to 25'c). the tank was 39" long 29" wide and 12" deep and work really well. i kept it clear bottom but with some rocks and slate hides with a bit drift wood. it was 7" long and i ran two internal 1800 LPH filters. water stayed perfect. i kept a few minow and zebra danios in there (they disappeared over time). the tank was kept in my bedroom, minimal lighting and i feed him on cani pellets then on to massivore. it took him about 2-3 weeks to eat. all good! it wasn't a planed buy although i have always wanted one i have never seen them for sale so when one came up i grabbed it.
now my goonch wasn't cheap and after buying it i did start to read threads about how they just curl over and die if not kept in prestine water etc and i started to get a bit anxious about how he was being kept so i carefully monitored everything and it all stayed fine but then i thought back to my reptile keeping days and how when things just didn't seem to go right with a harder to keep animal it was normally because you are following a guidelines that doesn't marry up to what nature is doing. so back to google but this time i was looking at the river systems on the HLG goonch.
so my tank all set up
once he had started feeding and putting on weight it became apparent that he would require a much larger tank in a quicker time than i have planed for but i knew where i could get my hands on a 260G tank for cheap, but i had no where to put it and this is really when my research started to work out.
before i get into that let me also add but the early summer months my tank heating was removed, the water temp was hitting around 25-30'c on its own and the cat was smashing food and growing an average 1" a month. but this also effected the oxygen levels in the water so more pumps were added . at some point i had to go away for about a month, no WC were done on the tank and my wife read my instructions wrong and feed the goonch the amount my adult dovii were supposed to get and he shoot up about 2.5" in the 5 weeks i was away. when i got back the water reading were all fine and a couple of days of 75% set me back on ease.
so on with my studies. a couple of interesting things came to mine when looking into these apex predators in their natural environment and a pattern emerged. i will split this down in to the following heading
- water temp
- yearly cycle
- growth to position
so let talk about water temp.
most people will agree that the water temp for a goonch should be subtropical if not cold water. also that the colder the temp of the water the more oxygen can be dissolved in it. so what i was interested in was first how cold and 2nd how this would effect the goonch as it grow.
so water temps in most of the HLG areas is cold all year round, with highs of 20 and lows of 5-7'c in winter, winter is going to be due to mountain run off and snow fall and in summer the lower water levels means it heat quicker.
another interesting thing about the goonch is it is quite often found in groups clinging to rocks under water normally at a 45' angle to the flow this is a trait seen in captivity too. but because they live in groups i have speculated that part of the diet (and i'm sure i read this ) is made up of cannibalising on the smaller members of its family. often i have read in care sheets how young goonch are more specialised than the larger ones so lets start with theory 1. the growth rate of a goonch is probably linked to the /breeding cycle of smaller fish, these small minnow fish will be occupying small pools on the outside of the river, these pools will heat quickly leading to an accelerated growth rate of the goonch feeding on these in the pools. if a small goonch has ample supply of food it can go from 7" - 20" in a matter of months.
so why is water temp so important???
well smaller goonch will need higher temp and probably less oxygen because they will be occupying the shallower warmer waters where the smaller feeder fish are, avoiding the larger goonch in the deeper water. as the goonch grows it will move ever closer to the deeper cooler more oxygen enriched water and its needs will change. there for we need to recreate this in the tank. this is another reason i thing the young goonch in an aquarium do really well to a point then they go down hill because they are not being transitioned. but more on that later.
yearly cycle,
well this is as you would predict really, when the smaller fish are breeding in the summer the goonch are feeding and growing, as the temps cool down this stops and the goonch become dormant over winter. in the spring when the water temp starts to climb the goonch feeding will kick in when the small fist start to appear again (theory 2)
growth to position.
so i touched on this up there ^^^^ but the growth of the goonch will decide where in the river it occupies. the deeper faster cooler parts will be occupied by the bigger fish with the shallower warmer less oxygen areas the smaller younger fish. when the winter colder temps hit they will all congregate in the deeper water because they won't be feeding so it safe.
now this was all speculation and just my thinking (and it may all be wrong) but it was time to try it out.
so i brought the 260G and a shed my plan was to have it set up so when the inside tank temp was near the outside temp i would move him across.
so by september he had reached about 19" and was ready to move, with the 260G all setup and a water temp of 20'c in both tanks i moved him over.
as expected he went instantly off food ( as per these fish when they are moved). so he is now in 260G with 5x 1800 LPH internal no heating sat in an uninsulated shed in september in the welsh valleys in the uk what could possibly go wrong?
well i did add a 40watt tube heater for under the tank but thats it.
ok so that was september. it's now april and he has been out there all winter. he got back on food till about mid october,then stopped, picked a spot and stayed there, 45' to the flow in the back corner. i monitored the water levels and did 25% water changes until dec when the temps dropped below 10'c. (air) the water itself stayed 5'c above air temp all winter and i didn't want to risk thermo shock, as he wasn't eating any way and i wasn't trying to force him too i just monitored the water and left him be.
by end of the end of feb we started to see a few warmer days coming in and i tried a few pellets but nothing.
by april it was almost 5 months no food or WC or movement notices, no tail drag marks in the sand nothing. but the weather had changed, we had a week of warm weather and i tryed food for the first time and got a bit of movement but no confirmed eating.
by the end of the first week i had done my first wc on the tank in months and i changed out 50%. during the process i disturbed him and he shoot around the tank, the first movement in 5 months witnessed so i guess hes awake?
i fished him out and he still 19" and doesn't look to have lost any body mass at all.
so today. well we have seen a drop in temp again (air temp is 12-13'c) but the water temp is about 15-16'c so the next step in my plan is to add some small minnow fish in a hope to get him feeding again ready for this summers growth spurt, who know we might be lucky and not have to buy a new tank this year.
please remember that the fish is not harmed and i personally would not have tryed this with out the research but i personally feel this is as close to nature as i can get it for this fish. any thoughts or opinions are very much welcomed.
cheers
