1 syllable:
bisch, bish, blish, brish, crish, disch, dish, drish, fisch, frisch, frische, gish, glish, guiche, isch, ish, kisch, kish, klish, knish, krisch, lish, misch, mish, phish, risch, rish, shish, slish, squish, swish, tisch, tish, trish, whish, wisch, wish, wishe, wisz, yeshe

2 syllables:
achish, affiche, assish, badisch, baitfish, barfish, basisch, batfish, beardfish, billfish, blackfish, bladefish, blindfish, blobfish, bluefish, boarfish, bonefish, boxfish, bugfish, burrfish, catfish, cavefish, chemisch, chenfish, clingfish, clownfish, coal-fish, coalfish, cod-fish, codfish, commish, conchfish, crampfish, crapefish, crawfish, creekfish, crossfish, dalgleish, dealfish, delish, demisch, dogfish, driftfish, drumfish, dunfish, episch, fallfish, filefish, finfish, flamefish, flat-fish, flatfish, fly-fish, flyfish, foolfish, foxfish, frogfish, frostfish, gamefish, garfish, ghostfish, gibfish, glassfish, globefish, glofish, goatfish, goldfish, goosefish, greenfish, ground-fish, groundfish, guardfish, half-fish, handfish, hawkfish, headfish, hektisch, henfish, hogfish, hornfish, horsefish, houndfish, icefish, inkfish, irisch, jackfish, jagdish, jawfish, jewfish, kelpfish, kingfish, klipfish, komisch, ladish, latish, logisch, lumpfish, lungfish, magisch, mcclish, mclish, mcnish, milkfish, monkfish, moonfish, mousefish, mudfish, nephish, netfish, numbfish, nymphish, oafish, oarfish, offish, oilfish, omish, pearl-fish, pearlfish, penfish, pigfish, pipefish, pondfish, pork-fish, porkfish, praktisch, prowfish, pupfish, queenfish, ratfish, redfish, rockfish, rosefish, roundfish, sailfish, saltfish, sandfish, sawfish, scaldfish, schreibtisch, seerfish, seirfish, shanklish, sheatfish, sheathfish, shellfish, shrimp-fish, shrimpfish, skullfish, sleevefish, snailfish, snake-fish, snakefish, snapfish, snipefish, soapfish, spadefish, spearfish, spikefish, spoutfish, squawfish, stammtisch, starfish, still-fish, stingfish, stockfisch, stockfish, stonefish, studfish, suckfish, sunfish, surffish, swellfish, swinefish, sword-fish, swordfish, tangfish, thing-fish, thread-fish, threadfish, thunfisch, tierisch, tilefish, toadfish, tongue-fish, tonguefish, trunkfish, tubfish, twofish, unwish, waifish, wallfish, weakfish, well-wish, wheyish, whitefish, wingfish, witfish, wolffish, wolfish, wormfish, wreckfish

3 syllables:
akustisch, allergisch, amberfish, angel-fish, angelfish, anglerfish, archerfish, australisch, balloonfish, barbarisch, barrelfish, battlefish, bishop-fish, bottomfish, butterfish, candlefish, chucklefish, cigarfish, convictfish, cornetfish, creole-fish, cuddlefish, cutlassfish, cuttlefish, damselfish, dandyish, devil-fish, devilfish, doctor-fish, doctorfish, dogmatisch, dollarfish, dolphinfish, dragonfish, dramatisch, einheimisch, elastisch, elektrisch, endemisch, firefish, flying-fish, footballfish, frankenfish, guitarfish, harvestfish, hatchetfish, icejjfish, interwish, jackknife-fish, jellyfish, jewelfish, ladyfish, lancetfish, lanternfish, leatherfish, lemonfish, lionfish, lizardfish, make-a-wish, moralisch, muttonfish, narzisstisch, needlefish, overfish, oyster-fish, oysterfish, paddlefish, parrotfish, pilotfish, platyfish, politisch, pollyfish, pragmatisch, pricklefish, pufferfish, quadratisch, rabbitfish, rainbowfish, razor-fish, razorfish, ribbonfish, roosterfish, rudderfish, sablefish, scabbardfish, silverfish, skilletfish, snobistisch, soldier-fish, soldierfish, spezifisch, squirrelfish, standoffish, sturddlefish, suckerfish, superfish, surgeonfish, swallowfish, tanglefish, tartuffish, tartufish, thunderfish, tigerfish, tintenfisch, tokenish, tokhtamysh, tovarisch, triggerfish, trumpetfish, ungarisch, vegetarisch, viperfish, weaverfish, whistlefish, yellowfish, yokelish

4 syllables:
achromatisch, akademisch, allegorisch, anekdotisch, aromatisch, automatisch, biologisch, buffalofish, butterflyfish, cardinalfish, charakteristisch, filet-o-fish, mosquitofish, plentyoffish, porcupinefish, scorpionfish, telescopefish, theoretisch

5 syllables:
alligatorfish